bureau of minee IC information circular 8225 Ill

COPPER A Materials Skey

UNITED STATES DEPARTMENT OF THE INTERIOR

BUREAU OF MINES 1965 COPPER A Materials Survey This publication has been cataloged as follows:

McMahon, Albert Daniel Coppr, a materials survey. [Washington] U.S. Dept. of the Interior, Bureau of Mi[I9641 340 p. illus., tables. ,(U.S. Bureau of Mines. InfomtIon circular E2m Includes bibliography. 1. Copper. (Series) TN23.U71 no. 8225 622.08173 U.S. Dept. of the Int. Library

For sale by the Superintendent of Documents, US. Government Printing Office. Washington. D.C.. 20402-Rice $1.75 (paper cover) OFFICE OF THE DIRECTOR

UNITED STATES DEPARTMENT OF THE INTERIOR BUREAU OF MINES WASHINGTON. D.C. 20240

January 11, 1965

Hon. Edward A. McDermott Director Office of Emergency Planning Washington, D. C.

Dear Mr. McDermott:

In accordance with the agreement of April 15, 1955, between

the Department of the Interior and the Office of Civil and

Defense Mobilization, which assigned responsibility to Interior

for preparation and revision of Surveys covering 45 mineral

comnodities, the Bureau of Mines with the cooperation of the

Geological Survey has prepared and herewith transmits to you

the revision of Copper, A Materials Survey.

Sincerely yours, CONTENTS

Chsgt+ 3:-Primary copper resources--Con ...... rmcl al co per mines in the world-Con . Foreword drth Lerica ...... Introduction ...... united States...... Acknowledgments...... Arhm ...... Chapter 1.-Properties, commercial claaaifics- Michigan ...... tions, and uses of copper and copper base Montana ...... Nevada ...... New Mexico...... all?."~;~. ~ the metal. Prooerties of copper ...... North Carolina ...... Yroperties of copper powders ...... Pennsylvania ...... Commercial clansification ...... Tennessee...... Hv Utah_ ...... -" mcthod. of refining ...... By method of casting or processing- .. Canada...... Newfoundland ...... T- relating. to specific. kinds of coppers- Forms...... Quebec...... Refinery shapes...... Ontario...... Fabricator products ...... Manitoba.Saskatchewan ..... Grades and specification% ...... British Columbia ...... Copper base alloys...... Cuba...... Nature ...... Heiti...... Properties...... Mexico...... Wrought alloys...... South America ...... Casting alloys...... Bolivia ...... Commercial claasi6cation ...... Chile...... Wrought alloys...... Peru...... Casting alloys ...... E~mr...... Uses of copper and copper-base alloys.---- ustns...... Copper as an slloying element ...... Bm...... Copper compound#...... Finland ...... BibLopaphy ...... East Germany ...... Chapter 2.-History ...... IreLand ...... Prehistory and early history of copper .... Norway ...... Mining ...... Poland ...... Metallurgy.-- ...... Spain------.------Bronze ...... heden...... Brass ...... U.S.8.R ...... Growth of industry in United States...... Yugoslavia...... Technological developments ...... Asia...... ChIonolog, ...... Chins...... Bibliography...... Cyprus ...... India Chapter 3.-Primary copper reaouroes ...... Israel...... Geology ...... Japan ...... Types of deposits ...... Philippines ...... Lenticular deposits in schistose rocks...... Turkey ...... Sudbury nickel-copper deposits... Africa...... Native copper deposits ...... Angola ...... Bedded deposits in sedimentary Republic of the Congo ...... rocks ...... Federation of Rhodesia and Nyasa- Veins. oioes. and disseminations.- land ...... EKflect of dxi&t;on on copper deposits . Northern Rhodesia ...... Character of sulfides...... Southern Rhodesia...... Character of gangue ...... Kenya ...... Type of deposit...... Mauritania ...... Mineralogy ...... South-West Africa...... Copper minerale...... Uganda ...... Copper orea ...... Republic of South Africa...... World Fkservea...... Australia ...... Principal copper mines in the world ...... Bibliopraph ...... Chapter 6.-Supply and diatribution-Con, Pam Chapter 4.43econdary copper resources...... World Produetion-Continued Nature...... Africa...... 205 Kinds of scmn...... ubhc of the Con o...... 205 sources...... aeraiion of ~fodesis and Magnitude of industry...... Nyaaaland ...... 205 Accumulating pool ...... South-West Africa ...... 205 World reserve ...... Republic of south Africa...... 205 Bibliografhy ...... Other countries ...... 205 Chapter 5.- echnology ...... Oceania- ...... 205 Rospectingand exploration current ore search Auatralir ...... 205 techniques...... World Consumption ...... 206 Boring ...... United States ...... 208 Underground exploration ...... Foreim. countries ...... 214 Mine development ...... World Trade ...... 215 United Statea ...... 216 Imports ...... 216 Exports...... 217 .. Foreinn countries ...... 229 Concentrating...... 229 Flotation ...... Cbk-...... 229 Segregation process ...... Republic of the Congo...... 243 Hvdmmetallwv ...... Former Federation of Rhodesia . and NvasaLand ...... Rewvw...... Prim...... Smelting...... Stocke ...... Rag...... Chapter 7.-Structure of the industry...... Fabricating ...... United States Cop industry ...... Melting furnaces and casting...... Location and &%iption ...... Seamless tubes...... Mining ...... Rode andshapes ...... Smelting...... Rolling: Strip, sheets, and plates.. .. Refining...... Rolling operations ...... Fabrication ...... Pickling equipment...... Secondary copper ...... Finishing equipment ...... Marketing ...... Examples of rolling practice...... Ores and wncentrates ...... Electrolytically deposited copper sheet. Refined wpper ...... Pri oee ...... Wire fabrication...... CaItek ...... Preliminary forming by rolling ... Phvsioal and financial wmorate strub Wire-drawing benches...... ture by wmpaniea ...... Continuougdrawiog machines. ... American Metal Climax. Inc ..... Bus bars and commutators...... American Smelting and Refining Print rob...... Company_- ...... Scrap ...... The Anawnda Company ...... Bibliography ...... Appalachian Sulfides, Ine...... Bagdad Coppe~Coi+ ...... Chapter 6.r-Supply and distribution ...... Banner Mining Co ...... World production ...... Wthlehcm~~ Cornwall~~ Corn...... North America ...... Calumet & Hecla . Inc...... United Statea ...... Primary copper ...... Company ...... Secondary production- ...... Copper sulfate...... Canada ...... Ins-piration Consolidated Copper Mexico ...... w ...... Kennewtt Copper Corp...... (:uba ...... Magma Copper Co...... SoutlI America ...... Newmont Mining Cop- ...... Chile Phelps Dodge Corp ...... Peru ...... luncy Mining Co ...... Europe ...... $ennw ' Corp ...... Finland ...... Primary copper mill~and primary wire Norway ...... mi& ...... Principal associated Government and Spain ...... industry gmups...... Sweden...... ---...... Labor organizations ...... U.S.8.R ...... World copper industry ...... Yugmhvin ...... Growth of world wpper industry ..... Other countries...... Distribution of world produetion ..... Ash...... Location of world industry ...... Important foreign copper producing Japan ...... W~D~UM...... North America ...... Philippines ...... Canada...... Turkey...... Haiti ...... Other countriea...... Mcew...... CONTENTS

Cha ter 7.4 tructure of the industry-Con . Chapter 9.-Research and developmentCou. %orld copper industry.-Con . Federal Bureau of Mines ...... Im~ortantforeien comer... producing Other Government agencies...... ebmpanies..C6n . Rearch and development associatiom.- .. South America ...... Bibllopaphy ...... CMle ...... Cbapterl0.-Legislation and government pro- Peru ...... grams ...... Intmdudion ...... Belgium ...... Rdatious...... Bdgaria ...... Mining bws...... Czechoslovakia...... Immrt taxes ...... Ndand...... e ...... Frau* ...... tions ...... East Germany ...... West Germany ...... Government barter program ...... Hmgary...... Taxation ...... Income taxes ...... Nomay ...... Depletion allowance...... Poland...... Emloration and devrlo~mentcosts ... Spain...... ~eaeralloans and maits for ewlora- Swden...... tion. development; or mining ..1 .... United Kingdom ...... Income from foreign sources...... U.S.S.R ...... State income tax...... Yusoslav ia...... General ...~rooertvtax= ...... Ash ...... Severanoe taxes ...... China...... Government loan program ...... Cyprus- ...... Exploration loans...... In&- ...... Export-Import Bank loans ...... Ism4...... Publics-m ...... Japan ...... Collection and diaaernination of baaic North Korea ...... Re~ublicof Korea ...... Ph&ppin es...... Mine health and eafety ...... Twkey...... Foreien mineral laws...... Africa ...... Can& ...... Republic of the Congo...... CMle...... Northern Rhodesia...... Mexico ...... Republic of South Africa- ... Peru...... 0De.wia...... Republic of the Congo...... Federation of Rhodeeia and Nyaaaland . Australia~~~ ...... Tasmania...... Bibllowaphy ...... Chapter 11.-Strategic factors...... Cha ter 8 Employment and productivity .... Introduction ...... %mpiGment...... Development of copper controls ...... AUooation of copper...... E,"Zyment statistirn ...... Productivity ...... Control of scrap ...... Mine productivity ...... Conswation and limitation orders.... Production Requirements Plan ...... Concentrator productivity ...... Controlled Materials Plan, World War Smelters and refineries...... 11 ...... Bibliompby ...... Controlled Materials Plan, Korean con- Cha ter 9 Research and development ...... Biot ...... ?ndu& research ...... %wmntmk ...... US. companies...... World War I1...... The Anaconda Company ...... Korean con0ict ...... American Smelting and Refining Com- StockpjUng...... pany ...... Strategic Materials Act of 1939...... American Metal Climax, Inc ...... Reconstruction Finance Corporation Cerro Cow...... Act of 1933, amended ...... Copper Range Company...... Surplus Property Act ...... Inspiration Consolidated Copper Co .. Strategic and Critical Materials Stock- Kennecott Copper Cow ...... piling Act of 1946...... Newmont Mining Corp...... Preparedneea Programs...... Phelps Dodge Cop...... Sell Suficiency ...... Foreign companies...... Bibliography ...... CONTENTS ILLUSTRATIONS

. . 1. Basic stepewpper ore to finished product ...... 4 2. Major cop er mines of the world facing page 39 3. Rotarv d4...... I~llll~~1lll1l.l~lIII~~I~I~l~~~~~I~ ...... 83 4 . Utah "&pper open-pit copper Nine. Utah ...... 5. Chuquicamara mine, .4tacama Dwert. northern Chile ...... 6 . Pllrn of hated, drille~i.and blasted holes ......

7. ~ Vertical~~ ~~- srcrion of orimarv drill hole ...... 8 . Inclined ski^ hoist:Chini~ine. N . Mex ...... 9 . Block-oavingmethod ...... 10. Block developmfnt. all-gravity ayarem ...... I1. Slusher-grxvlty block, threc-bench rarse dcslgu ...... I2. Dianramatre skerch of block-mvtun svswru of the El Tenreute mine . Sewell. Chile . 14 . Squawt ato i ...... 15. Miesion mill... B)odsh~~i...... 16. Miasion mill gnod~ngbay ...... 17 . Miasion niiU flourtiolr section ...... 18. Discharging and charging Pierce-Smith convrnera ...... 19. Pouring blister copper at rhe Dalklwsh copper sruelting work, U.S.8.K ...... 20 . FJectrolytic refinery, Baltimorr, Md ...... 21. Electrolytic wfincry, Perth .4mbuy, N.J ...... 22 .~ Electrolvtie~~~ . refioerv .. Nonlsk . U.5.S.B ...... 23 . Vertical casting of copper cakes ...... 24 . Principle of Mannesmann process ...... 25 . Mannesmannmachine...... 26 . Extrusion ms 27. Draw benc%-.-l~::::::::::::::::::::::::::::::::::::::::::::::::::::::: 28 . Extrusion shapes ...... 29 . Automatic rod draw in^. finishing. and curling machines ...... 30. Hot-breakdown rolling. scalping and conveying copper snd braas plat- ...... 31...... Roll arranwments ...... 32 . Rolling cl&tolerauee stripmetal ...... 3LJ . Elcetmlglivally depositing thin copper shcet ...... 34 . Breakdown rollin8 of whbar to md ...... 35 . 1J.S. production, consum tion, and onrr of copper, l91C-60 ...... 36 . US. pmducrion of re~ncJcopperfrom prirnar.~aud secondary source materials .. 37. Consumption of copper in 501th Auwricii, Euroire, U.J.Y.R., and Asia, 1951-60 ..

1. Clrasfication of copper ...... 2 . Composition and forms of wrought copper-baee.. alloys...... 3. Cast-copper-brae alloys ...... 1 ...... 4 . End-uses of copper, 1958...... 5 . Coppercompounda and their uses ...... 6. Princi~alcoo~er .. minerdB ...... 7. World copper reserves ...... 8. Trend of U.S. copper-reserve rstimates ...... 9 . Coneumption of old scrap, ahorr cons ...... 10. Estimatrd acetimulation of cotroer-in-use in the Unitpd States. 184&19613 ...... 11. Coo~erores snd co~perDrodtiied in the United States. distributed by principal 12. Elecvowinuing of copper ...... 13. Matte wcl convcrrer slag analyses ...... I4 Analvscs of var~ouvtv~rs .. of eunner.. for anode furnace ...... 15. Anal$ses of anodes ...... Id . Elrctrulyti~. refining of copper ...... 17. .Awrags percentage of scwp gu~~r~redwhen casting copper aud copper.bas t. alloys

rake*~ ~~ ~~ -~~~-- ...... into l,illets . sl.~t,s. slid ..to he far, ricatrd into rooocr-dlou.A. ~~~ " urodortar-~--~~- 18 . ~;e&e percknta&of scrap generated in fabricating~capperand alloy products from the cast billet or slab to finished size ...... 19. Practical maximum limits of scrap utilization in copper and brass fabrication- .. 20. Percent of total world production by leading countries ...... 21. Salient copper statistics ...... 22 . Mine nroduction bv State of recoverable CODDer.. in the United States. short tons. . 23 . World copper mine production. short tons ...... 24 . World smelter production of copper, short tons ...... CONTENTS

Pam Copper ore sold or treated. method of treatment. and recoverable metala ...... 187 Smelter production of oopper from domestic ores in the United States...... 190 Copper-produced by primary smelters ...... 190 Prirnarv. and secondarv comer produced bv nrimarv refineries in the United . -A . . . stat&, short tons...... Copper.. cast in forms at primary refineries in the United States, thousand8 of short toris ...... 8eeundary copper produced ilr thc Uuilcd Stales, abort tona ...... ('WUCT recovered inm scran. .nroctased in the Unitd Skrua,. by. kind of scrap aud fom.. of recovery. short tons ...... Production of secondary copper and copper-alloy products, short tons...... Composition of secondary copper-alloy production, short tons ...... Production of copper sulfate, short tom...... Production . shipment . and stocks of copper sulfate, short tons...... Shipments bf copper sulfate reported byproducing companies. short tans...... Copper producril~(ruineoutpui) in Canhda. by 1'1ovium. short tons ...... Copper comumptron of the world. 1926-3b. tlou&n (1s of shon tona...... Conrmr..rr....-.-. couwmntiort ...... of the world . 1946X". tllousand~of *I~ort tor^ ...... Primarv refined-conoer sunolvland withdrakals on domestic account, short tons . A . .... ~efinedcopper consumed, by class of consumers. short tons ...... 1 ...... Consumption of purchased copper-base scrap gmss weight in short tons ...... Consumption of copper in the United King om, short tons ...... Use of copper in Japan, thousands of short tons ...... Conner (unmanufactured). . imnorted. into the United States in terms of copper.. content,.. short tons ...... Copper (uamanufactured) imported into the United States, by class and country in terms of copper content, short tons ...... Copper (unmanufactured) imported into the United States, by countries in terms of copper content, short tons ......

Brass and copper.. scrap. imported. into and exported from the United States, shmt tons ...... Exports of insulated wire and cable by countries, short tons ...... Copper exported from the United States, short tons ...... Refined copper exported from the United States, by countries, short tom ...... Copper-base alloys, including brass and bronze, exported from the United States, ~ . by classes ...... Unfabricated cop er base alloy ingots, bars, rods, shapes, plates, and sheets exported from tEe United states ...... Copper sulfate (blue vitriol) exported from the United States ...... Imports of copper into the United Kingdom, by countries, short tons ...... Exports of refined copper from Canada, short tons ...... Exports of copper from Chile, short tons ...... Exports of copper from Republic of the Congo, short tons ...... Exports of copper from Federation of Rhodesia and Nyasaland, short tons ..... Monthly average copper prices of custom smelters, cents per pound, delivered ... Average yearly quoted prices of electrolytic capper, average weighted prices of refined CODDeI delivered in the United States, including prices adjusted by the wholesale;bdex. and for spot copper at London. cents p61 pound...... Stocks of copper at primary smelting and refining plants in the United States at end of year. short tons...... Stocks of copper held by fabricators at end of year, short tons ...... Consumer stocks of copper-base scrap at yearend, gross weight, short tons ...... Government stocks of copper, 1942-62 ...... Stocks of refined copper in the United Kingdom, short tons ...... Stocks of refined copper outside the United States, 1947-62 ...... Principal copper producers in the United States and disposition of their copper, 1962...... Twenty-five leading copper-producing mines in the United States in 1962, order of output...... Principal copper-producing companies in the United States, 1962...... United States primary copper smelters ...... United States primary copper refineries ...... Principal sellers of copper in the United States and brands sold, 1962 ...... Primary copper milla ...... Primary wire mills ...... Principal Government and industry groups concerned with the copper industry . Organization data of principal unions connected with the copper industry ...... Union affiliations at major copper mines, smelters, and refineries ...... Twenty-five leading copper producing companies in the world, in order of 1960 output, short tons ...... Foreign copper smelters and refineries...... Employee and injury data at underground and open-pit mines ...... CONTENTS

Com~arisonof mine efficiency. by. block caving- with other mining- methods in Blitte district ...... U.S. copper mine productivity-wages and labor cost, 1911-60 ...... --.... Productivity data of copper concentrators in the United States, 1943-60...... Productivitv data of smelters and relineries (combined) .-.--...... -. Copper indktry employment data..--...... --. .Lo...... -....-. Rate. of dut upder Tari5 Act of 1930 and important tax rates under Internal Revenue %de of 1954, modified by General Agreement on Tariffs and Trade (GATT) ...... Salient ststistics covering bonus psyments of the Government, 1942-47-. --..-. Contracts for expansion and maintenance of supply of copper under Defense Pm- duction Act of 1950...... Import and export balance, 1939-61 ...... COPPER A Materials Survey

Introduction

This survey is one of a series of Bureau of Mines publications designed to serve the needs of Government and industry for comprehensive infor- mation on mineral commodities and activities. Copper, a versatile metal, has been vltal to all civilizations from pre- historic times to the present. Its essential value in antiquity and until the nineteenth century arose from its ma~eabityand ease of working, its corrosion resistance and durability, its attractive colon in alloyed and unalloyed forms, and, of course, its avadability. The principal uses were for tools, utensds, vessels, weapons, pipe, statuary and other objects of art, and for building and architectural pur oses where formability, permanence, and beauty were necessary qualities. btilization of copper based on these ,physical and mechanical properties has grown tremendously for, commercial, structural, mechanical, architectural, and art items; and its capaci,ty for forming numerous all0 s has led to a myriad of applications from miniature ,copper and brass eye9 ets to huge bronze battleship propellers. The early nmeteenth century marks the epoch of the greatest use of wpper, transmitting electrical energy. This particular pro erty of wpper is fundamental the spectacular growth of the electrical in tlustry and all associated mdustnes relying on electricity for power, light, and heat. More than half of all copper produced is used for transmission of electricity. The copper industry has been able to expand along with the mounting demand because of the ever mcreasmg discovery of resources m the world and advances in mining, metallurgical, and fabricating technologies. World production and consumption rose progressively from about 18,000 tons in 1800 to more than 4.5 million tons in 1960. The estimated world reserve of primary copper has more than doubled since 1935, beimg 212 million tons in 1960. Ninety percent of this reserve is credited to eight countries-the United States, Canada, Chide, Peru, the Soviet Union, Poland, Northern Rhodesia, and the Republic of the Congo. The United States share is 32.5 million tons of copper in ore, avera ng approximately 0.9 percent. Another reserve being accumI,? ated m the mdustrial countries of the world is copper products now in use that will eventually be discarded as scrap and become available for recovering secondary copper. In the United States this resource of more than 30 million tons, provides about one-fourth of the annual supply.

I Phmleal sdentlat, Blanch of Nmfm08 Metals. Boream of Mines. Washington, D.C. Wort on manusczipt mrnpleted July 1W. or oxidized ores. They are type of copper-bearing mineral, and they may be desi ated as high grade or low grade, primary or seaondary, or disseminated, repy acement, vem, massive sulfide, nat~vecopper, and complex. Although many copper minerals are known, relatively few are commercially significant. The pre- dominant copper sulfide minerals found in the sulfide ore de osits of the world are chalcopyrite, chalcocite, hornite, cnargite, and covezte; the principal oxidized minerals are chrysocolla, malachite, and azurite. Antlerite, ata- eamite, and brochantite are important oxidized ore minerals of some deposits in Chile. The copper-bearing ores of many deposits contain significant values in minerals of other metals that are recovered as hyproducts or coproducts in concentrating, smelting, and refining recesses. Metals recovered from copper ores as byproducts include iron, lea$ zinc, molybdenum, nickel, cobalt, gold, silver, the platinum group metals, selenium, tellurium, and arsenic. Most copper ores are mined from large low-grade deposits, which are the source of about 80 percent of the annual world production of primary copper. The economical recovery of copper from such ores requires mass extraction and treatment processes. Deposits nes? the surface are worked by open-pit mining; caving or other large-scale mhmg methods (cut and fdl, shrinkage stoping, room and pillar) are used for underground mininq of deep ore bodies. The metallurgical processes for recovermg co per meta from its ores are concentrating, smelting, and rehimg for sulficf e ores and leaching followed by chemical precipitation or electrowinning for oxidized ores. The final refinery product is almost pure wpper (99.9+ percent) iq refinery shapes (wirebars, billets, cakes, slabs, ingots, and ingot bars), whch are used for producing copper wire and copper and copper-base do , semifabricated products such as strip, sheet, plate, tube, rod, and shapes. dpe1 illustrates the sequence of operations followed to obtain copper roducts from co per ore. The largest copper producer and consumer in tg e world througE out the 1925432 period was the United States. Before World War I1 mine production and the recovery of sewndary copper were adequate for domestic requirements and provided substantial quantities for export. When the United States entered World War 11, however, large supplies of wpper were required from abroad and the United States became a net importing nation. This situation continued through 1960. Axproximately one-half of the total United States supply of wp er is derived from omest~cmine production; a little more than one-fourth is ogtained from imports; and about a foyth is secondary copper recovered from old scra Mine productive capacity m the United States has not changed substantiafi since World War I, according to peak production years associated with the wars and other times of increased industrial activity. Be y,ing with 1916 the mines produced about 1 million tons of copper annua y m 1916, 1929, 194243, 1955-57, and 1960-63. However, because of the development of more e5cient mass mining techniques and equipment, mine productivity, in output of copper per man hour, has increased almost fivefold. Secondary copper is produced from new and old scra , the two general classes of scrap copper. Old scrap wnsists of metal articf' es that have been discarded because of wear, damage, or obsolescence, usually after serving a useful purpose. New scrap is generated in manufacturin items for con- sumption and reenters the processing and fabrication cycf e as run-around copper which does not contribute to new supply. Only cppper from old scrap, whether in unalloyed or alloyed form, is a real addltion to supply. There has been no sustained increase in the supply of sewndary copper for many years. Smce 1941 the recovery of wpper from old scrap has fluctuated mostly between 400,000 and 500,000 tons a year, reaching a maximum of 515,000 tons in 1955-a period of high prices for copper. Imports have come largely from properties owned by U.S. investors in Mexico, Chide, and Peru and from Canada. Chile has been the principal source, followed in order by Canada, Peru, and Mexico. In recent years significant quantities were furnished by Northern Rhodesia, the Republic of South Africa, and the Philippines. The United States exports refined comer to many countries-most of it destined for the United Kingdom,- West Gkany, Itali, France, and Japan. Consumption of wpper in the United States was at its hi hest during World War 11. Since then, except for a few years, .it has followef a declining trend caused to a marked depe by the substitution of alummum, steel, plastics, and copper-clad materials for largeuse items. The predominant users of co per are the electrical industry, the budding construction and automotive

--~~ in8ust.ries..~ and ~ manufacturers of industrial eoui~mentand su~~lies.Wire mills and brass millsusually account for more'tcan 95 percentAd total con- sum tion, wire mills having 50 percent or more in most years. borld consumption of copper increased almost 50 ercent from 1954 through 1962, principally because of the flourishiig in&strial activity in Europe and Japan. The resultant new demand was met by a similar growth in world production, largely from expanded output in Canada, Chile, Peru, Northern Rhodesia, the Republic of the Congo, U.S.S.R., China, Australia, and the Philippines. In the United States approximately 200 fims are engaged in producing and selling rimary copper. Principal segments of the industry are mining, smelting, re #n ing, fabricating, and marketing. The million tons of primary copper ~roducedannually comes from large operations. Of 196 copper mines reporting roduction in 1962, the 25 largest mines accounted for 97 percent of the totaP output; the first 10 produced 74 percent, and the first 5,48 percent. A total smelting capacity of 8,800,000 tons is provided by 20 smelters and the total refining capacity consists of 1,963,500 tons at 12 electrol tic refineries and 371,000 tons at 6 fire refineries. About 35 companies in the 6nited States are recognized as the important fabricators and users of primary copper; this they process into cop er and copper alloy forms of sheet, strip, rod, tube, wire, and extruded and ro Ped shapes. Some of the larfer, fabricators are amated with the major copper producers who thus have acillties for processing ores from the mines to the hished copper and brass products. Recovery of scrap copper constitutes an im ortant branch of the copper industry in the United States. Old scrap col? ected by hundreds of scrap dealers is processed into secondary copper by primary smelten and refineries, secondary smelters (brass and bronze ingot makers), and copper mdk. Government legislation and programs involving segments of the wpper industry usually comprise regulation, taxation, or aid to promote economic stability or to maintain national security. Some examples are the mining laws that regulate title, exploration, development, and extraction of ores from deposits on Government or Indian lands; import taxes levied for protection from foreign competition and reduction or suspension of such taxes for trade considerations; tax concessions granted mining enterprises for depletion in the Internal Revenue Code; laws regulating malpractices in securities and financial markets and prohibiting activities restraining trade, monopolies, and unfair trade practices. In emergency periods, such as World War I1 and the Korean War, price, export, import, distribution, and use controls were established for wpper. Public Law 520, July 23, 1946, authorized acquisition of strategic and critical materials (including copper) for the Strategic Stockpile, and the Defense Production Act of' 1950 provided for Government assistance in exploration of wpper deposits, development and production loans, and guar- anteed price contracts. The copper supply outlook for the near future in the United States is encouraging. This view is based on an estimated ore reserve containing 32% million tons of copper, an annual availability from secondary sources (old scrap only) of 450,000 tons, and a reserve of 1,142,000 tons of copper in the nahonal stockpile. Also, the increased ore reserves and expanded wpper production in Canada, Chile, and Peru provide ample sources of imports in the Western Hemisphere. MINING

Loading The ore body 1s broken up by The ore,averaglng about 1 per- The can of ore are hauled to blasting. cent copper. 15 loaded onto ore the mlll. can by electroc shovels.

The ore is crushed to pieces The crushed 'ore is ground to The mlneral.bear~ng particles the size of walnuts. a powder. in the powdered ore are con. centrated. SMELTING

Roarling Reverberatwy Furnace Converter The copper concentrates (av- The roasted concentrate IS The matte is converted Into eraglng about 30 percent smelted and a mane, contain- blister copper w~tha purlty of copper) are roasted to remove ing 32.42 percent copper. IS about 99 percent. sulfur.^ produced. R LlSltR (OPPtR

'whm me lh itlmnldropptr mmilhe wr,. 11uIm101tab~I~rs.I~~~ld.Oho~Ilumer

~h~lal mm 01 nmolm cww art Refining Furnace Ekmoh/lic Refining ~9~iwd.e1...hn Ihmw ir tokuYdW Blister copper is treated in a Copper requiring further treat. ~IWIU~Imdclm, marm whm mc~r ref in in^ furnace: men1 is sent to me electrolytic mDlr m pnUnl m mn~r~tnlowll*r 10 ""LI !&.desRbC FABRICATING REFINED COfffR

Dmwing Exhvding Fire refined or electrolytic copper andlor brass Sheets, tubes. rcdsand wire are further fabr~cated la mixture of copper and zinc1 is made into into the copper articles you seein everyday use sheets, tubes, rods and wire.

Flon~E1.-Basic Steps-Copper Ore to Finished Product. (Courtany, KeMecot oopper corp.1 ACKNOWLEDGMENTS

The author and the Bureau of Mines acknowledge with gratitude the assistance rendered by the following firms and their staff experts for reviewing various sections of this survey and submittin invaluable comments, corrections, and suggestions. American Smelting and %ehing Company, The Anaconda Compnny, Anaconda American, Brass Company, Anaconda Wire and Cable Company, Bridgeport Brass Co., Copper and Brass Research Association, Chase Brass & Copper Co., Inc., International Copper Research Association, Kennecott Copper Corp., Phel s Dodge Corp. The critical reviews furnisB ed by personnel of the Copper Division and the O5ce of Industrial Mobilization, both of the Business and Defense Services Administration, US. Department of Commerce and the Federal Geological Surve are sincerely appreciated. 'I%e author wishes to acknowledge the general statistical assistance in organization of tabular data throughout the manuscri t, as well as the develop- ment of the text and compilation of statistical tables !or chapter 6, provided by Gertrude N. Greenspoon, supervisory statistical assistant, Division of Minerals. CHAPTER 1.-PROPERTIES, COMMERCIAL CLASSIFICATIONS, AND USES OF COPPER AND COPPER BASE ALLOYS

NATWE OF THE METAL metal ranges fmm crimson or scarlet to various shades of blue and brown. Thin films of copper Copper is one of the few common metals that appear greenish-blue by transmitted light; hdsits greatest application in the commercially molten copper has a golden color; and wpper we rather than the alloyed form, principally vapor is green. The compact metal has a gecause of its superior erformance as a con- bright metallic luster and takes a bright polish, ductor of electricity. 2owever, metals such as which soon tarnishes when exposed to air. Old zinc, tin, and others readily alloy with copper surfaces often have an orange tinge due to a to form the widely used brasses and bronzes. 6lm of cuprous oxide (Cu20). Full oxidation Copper is an important alloying element in a of a surface causes formation of a film of the large number of alloys having metals other than black cupric oxide (CuO). Extended exposure copper as the principal component and mpper to weathering produces a green (patina) surface and copper-base alloy powders are formed lnto deposit which varies depending on the atmos- structural parts. This versatility and the ex- phere but the principal constituent is basic cop- ceptional service qualities inherent in the metal per sulfate with traces of baaic wpper carbonate are res onsible for its important role in the in- (malachite) for most atmospheres. Near salt dustri a! economy. water the amount of sulfate may be sharply reduced, with the carbonate increased substan- PROPERTIES OF COPPER tially, and large amounts of basic wpper chlo- ride (atacamite) are included. In rare in- The properties of copper having major signifi- stances, basic copper nitrate has been reported cance are its high-electrical and thermal con- where copper is exposed near power stations. ductivities, corrosion resistance, good ductil- Grain size, fabricating method, and mechan- ity and malleability, and high strength. In ical surface treatments (polishing, buffing, and addition, copper has a pleasing color, is non- vapor blasting) also affect the fin~shedcolor. magnetic, and is easily hished by lating or Combinations of alloy and mechan~caltreat lacquering; it can be welded, braze$ and sol- ments provide an unusual range of natural eqlor dered satisfactorily. Certain of these basic finishes for copper; chemical treatments provlde properties can be improved for many applica- additional colors and finishes. tions by alloymg mth other metals. As a The density of commercial wppers Janges consequence the popular commercial brasses, from 8.4 to 8.94 grams per cub~ccentlmeter. bronzes, copper-n~ckelalloys, and nickel silvers Cast tough-pitch copper contams about 3 to 5 have been developed. percent voids or gas holes, by volume, and such copper will have an apparent density of 8.4 to Physical constants of copper: Chemical symbol...... Cu 8.7. The voids close during rolling; after Atomic number...... 29 working and annealing the density of tough- Atomic weight ...... 63.54 pitch copper 1s 8.89 to 8.94, depending on the Valenm...... 1 & 2 residual oxygen content. Copper containkg Crystal structure...... Facecentered cubic, 0.03 percent oxygen has a maximum dens~ty Density, annealed, 20' C...... 8.89 of 8.92, and values as high as 8.9592 have been Hardness, MohL ...... 2.5-3 obtained for pure copper. The denslty of Melting ~int,~~C ...... 1083 Boiling point, C...... 2595 liquid copper is 8.22 near the freezing point. Electrical resistivity, 20' C, mi- The shrinkage of copper on solidification is crohm-om., annealed...... 1.71 4.96 percent. Electrical.-The high electrical conductivity Physical.-Copper is the only metallic ele- of copper, more than anything else, accounts ment besides gold having a rich natural co!or other than some shade of gray. The distmctive for its widespread use in the electrical field. red color of metallic copper is best seen, on a Only one metal, silver, is a better conductor in fresh or polished surface. Copper prec~pltated cross-section. Since aluminum has higher con- from solution is brownish red and the colloidal ductivity by weight, it is the principal rival of 7 comer for certain tvoes"A of electrical compared to losses in brasses and other alloys. inst'allations. The most severe cold working does not reduce The conductivitv of comer.. is ex~ressedin the conductivity more than 3 percent. percentages, thus goviding a convedent meas- The conductivity of copper by weight is ure of quality for electrical purposes and for surpassed by several light metals, notably comparison with other metals. The basis for aluminum. Relative conductivity values for rating is a mass conductivity standard adopted silver, copper, and aluminum by volume and in 1913 by the International Electrotechnical weight are: Commission and subsequently by the American Cmrdudiaitv pwccnt by- Metal: voz~nr weight Standards Association, American Society for Silver ...... 100 44 Testing Materials, and other bodies. The Copper ...... 94 50 standard mass resistivity is 0.15328 ohm Aluminum ...... 57 100 (meter, gram) at 20' C; that is, a copper wire Iron ...... 16 --- 1 meter long, weighing 1 gram, and having a resistance of 0.15328 ohm at 20' C. The value Thermal.-Copper is the second best heat of 100 is assigned to the reciprocal of this stand- conductor of all metals, again being surpassed ard resistivity, and conductivities of other only by silver. Comparative values for thermal specimens are stated in percentay ,of this conductivity for different metals at room tem- conductivity. This standard con uctivlty 1s perature (18' C) are as follows: designated the International Annealed Copper Heat Conductivity, ~al/cm/cm'/sec/~C: Standard (IACS). A standard density of 8.89 Silver ...... 1.006 grams per cubic centimeter was also adopted CopI...... 934 to permit expression of the standard in terms of Gold ...... ,705 both mass and volume units as in the following Aluminum ...... 480 equivalents : 0.15328 ohm (meter, gram), 875.20 ohms (mile, Important thermal constants of copper are: pound); 0.017241 ohm (meter, sq. mm), Melting point...... Bailing point...... 1.8241 mimhm (cm, cmx);0.67879 microhm Latent hest of fusion. (in, in'), 10.371 ohms (ft, mil)-all at 20' C. Heat capacity ...... Linear coefficient of ASTM specifications require all copper in- expansion. tended for electrical use to meet a 100-percent Themal conductiv- conductivity minimum. Commercial coppers ity, lSOC. designated for electrical purposes have con- ductivities between 100.5 and 101.8 percent. Mechanical.-One or more of the qualities Very high purity copper prepared for research of strength, hardness, ductility, malleability, use has a conductivity of 102.3 percent. and ease of joining usually are desired with the The electrical resistivity of metals increases other physical and chemical properties of with temperature, the average change for copper. The properties denoting plastic defor- copper between 0' and 100' C. being 0.42 mation are rated highest, and those referring percent for each degree. At extremely low to strength are rated lowest in fully annealed temperature the electrical resistance almost metal. vanishes for copper (and other metals). Some Pure copper is not particularly strong or resistivity values at temperatures from almost hard in the annealed condition, but both absolute zero (-273' C) to that of molten strength and hardness are increased con- copper are: siderably by cold working. Commercial cop- Rui,tisitv. pers in the annealed state have tensile strengths Temperatures, T: nimh-m -258.6 ...... 0.014 from 32,000 to 35,000 pounds per square inch. - 206.6 ...... ,163 Values to 75,000 psi have been obtained for - 150 ...... ,567 severely cold worked copper. Annealed copper - 100 ...... ,904 +20 ...... 1.7241 has a Brinell hardness of about 42, which +lo0 ...... 2.28 can be increased to more than 100 by cold 0 ...... 2.96 working. Copper is little hardened by quench- +500 ...... 5.08 ing or other heat treatment. The tensile ...... 9. 42 +l,500 @quid) ...... 24. 62 strength and elongation values obtained by cold working the three basic commercial types Source: Handbook of Chemistry and Physics, 196M1, The Chemical Rubber Publishing Co., Cleve- (tough pitch, deoxidized, oxygen free) are and, Ohio, 42 ed., 1960, p. 2590. identical from a practical standpoint. This equivalence in mechanical properties is~espon- Copper may be cold worked to great extremes sible largely for continuance of the histoncal with but a slight loss of electrical conductivity, tendency to consider both oxygen- and PROPERTIES. COMMERCIAL CLAGSIFICATIONS, AND USE6 9 hosphoms-bearing coppers as commercial processes, using either copper-phosphorus or forms of the metal, and to reserve alloy desig- silver-alloy types of brazing filler metals. nation, for products having more pronounced (ASTM B260-56T and AWS A5.8-56T speci- alteration of physical characteristics. fications for brazing Uer metal.) B proper Annealed or hot-rolled electrolytic tough-pitch selection of the brazing process and der metal copper is very ductile High purity copper it is possible to braze oxygen-bearing copper is so ductile that it is di5cult to determine the without loss of strength due to copper oxide existence of a finite limit beyond which it segregation. cannot be cold worked. (No evidence of such Soldering with the common types of tin-lead a limit has been observed in wires drawn 99.4 solders is an effective and simple way of join- percent, which had developed a tensile strength in sections of copper. Selection of a particular of 75,000 psi.) Copper is very malleable which sofder will usually depend upon the operating allows the rolling or hammering of the fully temperature and other working conditions of annealed metal into very thin sheets without the required service as well as economic cracking. Although there are apparently no considektions. quantitative criteria for measuring malleability, Copper may he clad on other metals or may copper compares favorably with gold and silver be clad with other metals, in each instance to in acceptance of plastic deformation without achieve some special purpose. Copper cladding rupture. on steel is used to reduce the overall cost or Soft copper has very little elasticity or to increase the strength while maintainin the resilience, but cold working increases values high conductivity of copper. Copper clafding for both properties. Soft copper has an of aluminum combines the lightness of that elastic limit or yield point of 3,000 to 17,000 metal and the conductivity of copper. Copper psi, depending on the convention used in is clad with certain silver brazing alloys to defining these terms; there is little true elas- facilitate the brazing of special types of tools ticity, and even small loads may produce and improve their performance. some permanent deformation. Cold-rolled Chemical.-Copper has an atomic number copper has a yield point of 40,000 to 55,000 of 29 and an atomic weight of 63.54. It is the psi, and the Young modulus for hard copper is &st member of subgroup IB of the periodic about 16 million psi. table, being followed by silver and gold. Each The endurance limit, which is the maximum of these three metals form a univalent series of stress a metal will withstand without failure salts, hut copper also forms a bivalent series during numerous cycles of stress, is 11,000 psi and gold a trivalent series that are more for annealed copper. This can be increased stable than the corresponding univalent com- by work hardening to 15,000 psi for tough- pounds. The electronic configuration of copper pitch copper and to 19,000 psi for deoxidized is 2:8:18:1. Loss of the outermost electron copper. produces the cuprous ion Cu+, and a second Copper and many of its alloys may be joined electron may be lost in the formation of the by welding, brazing, and soldering. The weld- cupric ion Cu++. The formation of these two ing of oxygen-bearing copper requires special ions is an important factor in considering the techniques because the high temperature of corrosion behavior of copper. There are two the heated zone may cause rejection of the stable isotopes of copper, Cum, consisting of cuprous oxide to grain boundaries, weakening 29 protons and 34 neutrons, and Cum, with 29 the area. Success has been reported with fast protons and 36 neutrons. There are also welding processes when the welding time is so known to be at least eieht unstable (radio- short that virtually no oxide segregates, or when active) isotopes having tKe mass numbers 58, the segregation is so minor that the strength 59, 60, 61, 62, 64, 66, and 67. of the joint is not seriously impaired. Such Some of the characteristic features of the processes are helium- or argon-shielded arc metals in this group are: welding, a resistance in air method, and use of 1. They occur as native metal and may be a gas torch with a slightly oxidizing flame. separated from compounds with relative ease. Deoxidized and oxygen-free coppers are readily 2. They are not very active chemically. As oined by arc- and gas-welding processes and k.razing. Properly welded joints in oxygen- the atomic weight increases, the chemical ac- free copper will have strength and ductility tivity decreases. about 90 percent of the annealed strength of 3. Copper and silver oxidize very slowly in the base metal. The properties of the weld air at ordinary temperatures. may be greatly improved by cold working. 4. Their oxides and hydroxides are slightly The oxygen-bearing, deoxidized, and oxygen- basic. free coppers are readily joined by torch, 5. They form insolublechlorides, for example, furnace, dip, and twin-carbon-arc brazing CuCI. 6. Complex ions are readily formed, for ex- by oxidizing action to form soluble copper salts. ample, [Cu(CN),]-. Copper also forms complex salts with am- 7. Complex cations are formed with am- monium compounds and with c anides. In the monia, for example, [Cu(NHJ,]ft. complex copper-ammonium sa7 ts the copper is One of the main reasons for the wide use of in the form of a cuprammonium ion which bas copper and copper-base alloys is the excellent a deep-blue color. Cupric ions impart a resistance to corrosion displayed in a wide range greenish-blue- - color to the solution; cuprous ions of environments. Copper possesses very high are colorless. resistance to the atmosphere; to naturally Gc- Examples of complex cya~idesare the soluble curring waters, both fresh and salt; and to sodium and potassium salts N~CU(CN)~and alkaline solutions, except those which are dis- KCu(CN),. In these salts the copper is present tinctly ammoniacal. Behavior of copper in in the negative ion [Cu(CN),]; these complex acids is greatly dependent upon oxidizing con- cvanides are used in electrolvtes for electro- ditions which affect it adversely. It has good dating cop er resistance to many saline solutions. However, Cupric choke forms s soluble double chlo- copper offers low resistance to sulfur and sulfur ride with ammonium chloride-CuC1,. compounds, producing a corrosion product of 2NH,C1.2H20. The insoluble cuprous chlo- copper sulfide. It may be seriously damaged ride forms a similar compound with ferrous by solutions such as sea water and brine when chloride, and this makes possible the dissolving these move against it at high velocihes. of cuprous chloride in brines of ferrous chloride. Copper rare1 corrodes through galvanic Copper is fun 'toxic and is used more in action as a resuf t of contact with other metals. preparing agric3' tural fungicides than any In the electromotive series of elements, copper other metal. Compounds of other metals is near the noble end and normally wdl not (silver, mercury, cadmium, and others) may displace hydrogen from acid solutions. Copper be more effective fungicides but the popularity is cathodic to the commonly encountered of copper compounds is largely due to a fairly metaletin, lead, nickel, iron, zinc, aluminum, high degree of fungitoxicity, a low toxicity for and ma nesium-that can be used to displace most higher plants and animals, and a lower copper 9rom solutions of its salts. Mercury, price than most other metals of comparable silver, palladium, platinum, and gold-being effectiveness in disease control. below copper-can be displaced from their salt Effects of Impurities.-The conductivity, solutions by metallic copper. There are many tensile strength, and other properties of copper conditions, however, in which displacement does are affected to varying degrees by the presence not proceed in accordance with the common of impurities which may either (1) be dissolved electromotive series. The potential differences in the copper in solid solution or (2) be insol- between dissimilar metals vary, depending upon uble in solid copper. The most important of the nature of the corrosive environment. those in the first class are nickel, iron, arsenic, The crystal structure of copper is face- antimony, and phosphorus. The second group centered cubic, the cube side being 3.6078 A includes bismuth, lead, selenium, tellurium, at 18" C; the closest distance of approach of sulfur, oxygen, and oxides. atoms, 2.551 A. This is a close-packed struc- Oxygen is present in all commercial copper, ture, being one of two possible structures except in the deoxidized and oxygen-free grades. formed by the closest possible packing of uni- Its effect on the mechanical properties is not form spheres. Each atom has 12 equidistant great, slightly increasing the tensile strength nearest neighbors. The structure has the and reducing the ductility as the oxygen con- highest degree of atomic concentration and tent increases. In small amounts oxygen in- symmetry to be found in any crystal structure. creases the electrical conductivity of commer- Common gases such as 02,CO, SOn, and Hz cial copper, very likely by oxidizing other dissolve in molten copper. Some of these gases impurities and thus removing them from solid undoubtedly react with the copper or with solution. Large amounts of oxygen, however, other compounds; thus dissolved oxygen is reduce the conductivity by forming copper probably in equilibrium with Cu20: oxide, reducing the effective cross section of the metal. Sulfur, selenium, and tellurium, in general, affect the mechanical properties of copper and reducing gases such as CO and Hzreact with In amounts to 1 percent, selenium CuaO to form copper, CO,, and HzO. The and*verse?. te urium may be used for increasing nature and amount of gas remaining in copper machinability. just before it solidilies markedly affects the Bismuth also has a harmful effect on the properties of solid copper. mechanical properties of copper; it interferes Copper will dissolve in most acids when aided seriously with hot rolling and slightly with .PROPERTIES, COMMERCIAL CLASSLFICATIONS, AND USES 11 cold rolling. Its effect may be partly neutral- carbon dioxide and nitrogen behave as if they ized by additions of oxygen, arsenic, and were insoluble in copper. The influence of antimony. It is almost completely insoluble gases in copper is a complex problem of great in wpper. importance to producers of copper castings. On the whole, antimony is mother harmful On the whole, the amount of gas evolved in' metal, although it is sometimes added to casting should exactly neutralize the natural copper when recrystallization temperatures shrinkage of the metal on passing from the liquid are desired. Y amounts of 0.5 percent and to the solid state. higher it hardens copper, decreases its ductility, and lowers its electrical wnductivity. Anti- mony is similar in effect to phosphorus and PROPERTIES OF COPPER POWDERS arsenic and is intentionally added in small amounts (0.02-0.10 percent) to some high- The quality of metal-powder parts depends brasses for increasing resistance to dezinci- upon properties of the powders used. The fication. most important of these properties are: Arsenic is added intentionally to 0.6 percent Purity.-Clean particle surfaces insure good because of its slight hardening and stren then- wntact between particles (needed for optimum ing effect, especially in the cold-workej wn- mechanical properties). The presence of foreign dition. It raises the recrystallization tempera- particles must be held to a minimum, usually ture but has little effect on the ductility and malleability. It decreases the electrical specified. conductivit considerably. Arsenic is an ex- Apparent Density.-Apparent density (some- cellent inhixitor of corrosion by dezincification times bulk density) is the weight of the unit in leaded muntz metal, admiralty brass, naval volumeof powder andis of particular importance brass, and aluminum brass; 0.02 to 0.10 percent in the pressing operation. The lower the value, is added to these alloys for that purpose. It the greater the volume needed for a part of is not useful in the alpha-beta brasses because given size. it does not inhibit dezincification of the beta Compressibility.-Compressibility (ratio .of phase. volume of loose powder to volume of compact) Next to oxygen, silver is the most common is important for both fabrication and end prop- element in commercial wpper. It has negli- erties and is affected by physical characteristics gible effect on the mechanical properties and of powder particles and distribution of particle electrical conductivity but significantly in- size. Particle-size distribution affects press creases the rewystalhzation tem erature and feed, dimensional changes during sintering, prevents softening of wld-worke f material by porosity of the compact, and 6nal attainable short time exposure to heat. density and strength. The small amount of iron normally present Flow Rate.-The ease with which a metal in commercial wpper has very little effect on powder can be fed into the die is determined its mechanical properties. In larger amounts, by its flow rate. Low flow rates retard auto- to 2 percent, it hardens and strengthens copper matic pressing and may require the use of sli htly without destroying ductility, but it vibrating equipment. re2 uces the electrical conductivity, especially Sintering Properties.Sintering is usually in the absence of oxygen. done either in an inert, reducing, or neutral Lead is sometimes added in small amounts atmosphere or in a vacuum., The sintering to wpper to increase its machinability, but it temperature of metal powder,is critical; when should not exceed 0.005 percent if the wpper is metal-powder compacts are amtered, eithef m to be hot rolled; otherwise it will cause "hot the solid state qr in the presence of a mmor shortness." If operations are conducted at portion of a liqutd phase, smtable physical and room temperature, still larger amounts have mechanical properties must be obtained within little effect on the ductility of copper. It can predictable and reproducible dimensions. be rendered somewhat less harmful by intro- Green Strength.-Thia is the property of the ducing oxygen. powder to be handled without breakage after Gases have a great effect on the physical compacting and before sintering. properties of wpper, especially in castings. Mechanical and physical properties of sin- Hydrogen is very soluble in liquid copper but tered parts are closely related to the final denslty will not cause unsoundness in copper castings, that can be achieved. As the density of a in the absence of oxygen, unless the solubility in the solid state, which is high, is exceeded. metal powder part increases, strength also Carbon monoxide is probably soluble in solid increases, and at a density of 100 percent the and liquid copper to about the same extent and properties theoretically will be at least equal in the absence of oxygen is not harmful. Both to those of solid stock. COMMERCIAL CLASSIFICATION mechanical properties to some degree, whiie rendering certain impurities insoluble by con- By Method of Refining verting them to oxides. The scavenging effect The broadest commercial classification of is beneficial both to high conductivity and to copper is related to the method by which it is low-annealing temperature. refined. Thus, copper is described as electro- Oxygen-Free Copper.-Electrolytic copper lytic or fire refined: that is free from cuprous oxide, produced with- Electrolytic Copper.-Copper which has been out using metallic or metalloids1 deoxidizers. relined by electrolytic deposition, including By extension, the term is also applicable to cathodes which are the direct product of the fabricated products. The types of oxygen-free refining o eration refinery shapes cast from copper are as follows: Oxygen-free without metal catg odes, .; and products of fabricators residual deoxidants (OF), oxygen-free phos- made therefrom. Usually when this term is phorus bearing (OFP), oxygen-free phosphorus used alone, it refers to electrolytic tough-pitch and tellurium bearing (OFPTE), oxygen-free copper without elements other than oxygen silver bearing (OFS), oxygen-free tellurium being present in significant amounts. bearing (OFTE). The OF and OFS types are Fire-Refined Copper.-Copper that has been high+onductivity coppers. refined by a furnace process only, including re- Oxygen-free copper is produced either by finery shapes and products of fabricators made melting selected cathodes in the presence of therefrom. Usually when this term is used carbon or carbonaceous gases and then casting alone, it refers to fire-refined, tough-pitch in a reducing atmosphere or by coalesence of copper without elements other than oxygen specially prepared and treated cathodes under being present in significant amounts. heat and pressure. In the former method, the impurities are alloyed by the melting operation, By Method of Casting or Processing resulting in higher annealing temperatures than are encountered with the tough-pitch variety. There are three basic classes of commercial The net change in conductivity is negligible, copper. They are known as tough-pitch cop- however, since the tendency for loss caused by per, oxygen-free copper, and deoxidized copper; increased solubility of impurities can be offset there are several types of each available in re- by gains from elimination of cuprous oxide and finery shapea and wrought and cast products. regulation to allow partial oxidation of some Seventeen types are recognized by the American of the impurities, notably iron. It can also be Society for Testing Materials in its "Classifica- modiied during production by additions of tion of Coppers" which bears the designation silver, phosphorus, and so forth. B 224-58. This classification is shown in Coalesced copper (PDCP) is made by com- table 1. pressing specially prepared granular cathodes Tough-Pitch Copper.-Copper, that is, either in a reducing atmosphere while hot and then electrolytically refined or fire refined, cast in without previous melting by extruding through the form of refinery shapes, and that contains a a die into commercial shapes. The impurities controlled amount of oxygen for obtaining a mechanically trapped in the original cathodes level set in the casting. The term is also appli- are physically dispersed in unalloyed form in cable to the products of fabricators' products the extruded products. As a result, oxygen-free made therefrom. copper produced b this method has a conduc- The types of tough-pitch copper designated tivity advantage oP several tenths of a percent, by the American Society for Testing Materials and a low-annealing temperature. It is ex- are: Electrolytic tough-pitch (ETP); fire-re- truded to sizes for mill finishing and thus is fined, high-conductivity toueh-pitch (FRHC) ; not available in many of the standard dimen- fire-refined, touch-pitch (E"RTP); arsdnical sions associated with refinery shapes produced touch-pitch (ATP); silver-bearing, tough-pitch by casting. Alloying additions are also pre- (STP); silver-bearing, arsenical tough-pitch cluded by the nature of operations. The (SATPI; and casting (CAST). ETP, FRHC, extrusion operation provides an excellent sur- and STP are hich conductivity coppers and the face, free from laps and slivers which may only types used for casting wire ban (table 1). act as points of weakness in insulated coatings. Tough-pitch copper can be cast with a level, Consequently, a large proportion of coalesced set by adjusting the oxygen content between copper is used for manufacturing conductors normal limits of 0.02 to 0.05 percent. Because into wire, flatwire, bar, and strip. The products of its adaptability to high-tonnage melting and are also characterized by high-residual ductility, casting techniques it is the least expensive kind resistance to hydrogen embrittlement, and suit- to produce and has long been the standard ability for metal to glass seals. variety for producing wire, rod, plate, sheet, Deoxidized Copper.-Copper cast into re- and strip. The presence of oxygen affects the finery shapes, freed from cuprous oxide by PROPERTIES, COMMERCIAL. CLASSIFICATIONS, AND USE8 13

- Form in which available

From fabricators ASTM - CLass and type designa- tion In- gots Flat Pipe Rod Wire Bil- Cakes and rod- and and Shapes bars lets ingot lcts tube wire bars ------Tou h pitch: %~ectro~ytic-...... ETP XXXX XX XX Fire refined, high conductivity ...... FRHC X XXX XXXX Fire refined ...... FRTP .... XXXX X.. X Arsenical...... ATP, .... XX XX X ...... Silver hearing ...... 3TP X XXX XXXX

Silver-bearing- ~ arsenical...... SATP -.-. X X...... XX ...... CAST ...... X ...... Oxmen free: OF X XX X X OFP X XX X .-.-.- . X X ~ ------OFPTE .... Silvw bearing ...... om X X.. X X TeUurim bearing ...... OFTE ...... XX Deoxidiaed, phos horieed: ~igh-r~~du~phonpl~orus...... DHP X XXXX

Low-reaidtral &ohusohorus.. & ...... ~ - DLP .... XXXX Silver b&nu ...... DPS XX - X Arsenical ...... DPA .... XX ...... Tellurium bearing--- ...... DPTE . X X - 8omoe.. ASTM Standard8 1081, pt. 4 Nan-Famu Met-, p. 28l. using metallic or metalloidal deoxidizers. The material to be welded by gas, carbon-arc, or term is also applicable to fabricated products. metal-arc methods where both embrittlement The types of deoxidized copper are: Phosphor- and porosity would result from oxidation. bed, high-residual phosphorus (DHP), phos- Consequently, the quantity of phos horized phorized, low-residual phosphorus (TlLP). copper used for tube manufacture af'one, ex- phosphorized, silver bearing (DPS), phosphor- ceeds that of all other oxygen-bee or deoxldlzed ized arsenical (DPA), and phosphorized, tellur- types combined. ium bearing (DPTE). Deoxidized coppers (DLP and DHP) are TERMS RELATING TO SPECIFIC produced by dwxidiziig with sufficient phos- phorus to insure combination with all of the KINDS OF COPPERS available oxygen. The high-conductivit type, DLP, must contain very little residusYphos- The American Society for Testing Materials phorus, and the total content rarely exceeds (ASTM Standards 1961) has adopted ,de 0.011 percent of phosphorus. Greater amounts scriptive terms for identifying the principal are intentionally added to produce type DHP types of cast and processed coppers: which may contain 0.015 to 0.040 percent Hi~h-Conductivity Copper.--Copper which, in the phosphorus, resulting in a conductivity range snnealed condition, has a minimum electrical con- of 80 to 90 percent I.A.C.S. A significant ductivity of 100 per cent I.A.C.S. an determined in increme in annealing temperature is also ob- accordance with ASTM methods of test. tained which permits soldering of hard-drawn Cnsting Copper.-Fire-refined, taugh-pitch copper usually cast from melted secondary metal into ingot p~oduotswith minimum softening. The re and ingot bars only, and used for making foundry sldual phosphorus is most beneficial in pre- castings, but not wrought products. venting absorption of oxygen by the copper Phosphorized Copper.-General term applied to during hobworking and annealin operations, copper deoxidized with phosphorus. The most com- thus avoiding ernbrittlement &ring those monly used deoxidized copper. High Besidud Phosphorus Copper.-Deoxidized subsequent processes which require heating in copper with residual phosphorus present in amounts a reducing atmosphere. It is especially im- (usually 0.013 to 0.040 percent) generally sumcient to portant to provide a residual deoxidixer in decrease appreciably the conductivity of the'copper. 14 COPPDR

Low Residual Phosphorus Copper.-Deoxidized eop- per with residual phosphorus present in amounts Fabricator Products (usually 0.0134 to 0.012 percent) generally too small to Wire.-A solid ~ection, including rectangular Eat decrease appreciably the conductivity of the copper. wire but excluding other Eat products, furnished in Arsenical Copper, Phosphorous Bearing Coppw, coils or on spools, reels, or buoks. Flat wire may also Silver Bearing Copper. Tellurium Bearing Copper.- be furnished in straight lengths. Copper containing the designated element in amounts Tube.-A hollow product of round or any other cross- as agreed upon between the supplier and theconsumer. section, having a continuous periphery. Any of these alloyed coppers can be produced as Pipe.-Seamless tube conforming to the particular tough-pitch, oxygen-free, or deoxidized varieties. dimensions, oommeroially known as "Standard Pipe Sizes." The most important classification for wrought Shape.-A solid section, other than rectangular, forms of commercial copper and copper alloys sauare or standard rod and wire sections. furnished in is based on composition, the forms being desi stmight lengths. nated by long established names. cpmmo& Shapes are usually made by extrusion but may also he fabricated by drawing. accepted trade terms for the different kinds of Flat Products.-A rectangular or square solid section copper, and their nominal chemical composi- of relatively great length in proportion to thickness. tions, are as follows: Inoluded in the designation "Eat product" depending Accepted trade tern: co position. ~cncnt on the width and thickness, are plate, sheet, &kip, ana as Electrolytic tough pitch 99.90 Cu4.04 0 bar. Also included is the product known "flat IETP) wire." Bod.-A round, hexagonal, or octagonal solid section. Phosphorized, high-resid- Raund rod for further processing into wire (known a3 ual phosphorus (DHP). "hotrolled rod," "wire-rod," or "redraw wire") is Phosphorized, low-resid- furnished coiled. Rod for other uses is furnished in ual phosphorus (DLP). straight lengths. Lake ...... Copger Powder-Finely divided co~oer articles Silver bearing (l(C15). .. . Silver bearing (25-30). .. . Oxmen free (OF), no re- . . iidual deoxidants. Free cutting, lead bearing. 99.0 Cu-1 Pb Free cuttine. tellurium 99.5 Cu4.5 Te Grades and Specifications The various types of copper are graded by "--- ... -. Cadmium copper .-...... 99.0 Cu-1 Cd the American Society for Testing Materials Chromium copper ..-.....Cu-0.4 to 1.2 Cr principally according to their chemical com- Beryllium copper ...... Cu-1.8 to 2.05 Be position. Specifications adopted for these cop- pers are as follows: FORMS ASTM Designation: ASTM defines refinery shapes and fabrica- B4-42-Lake copper wire bms, cakes, slabs, billets, ingots, and ingot bars (must ton' products as follows: originate on the northern peninsula of Michigan). Refinery Shapes (a) Lou, Rcalalnnw Lake Copper-minimum purity of 99.900 pcrccnc, silver wing ~~ountc~las copper. Wire Bar-Refinery shoe for rollinn into rod (and &*(.Nd", w. subsequent drawing &to wbe), strip or-shape. ~i-1 Approximately 3)4 to 5 in. square in cross-section, ohm (meter, usually from 38 to 54 in. in length and weighing from warn) 135 to 420 lb. Tapered at both ends when used for Wire bars...... -.-.----.--...-. 0. 15328 rolling into rod for subsequent wire drawing and may Cakes, slabs, and billets: be unpointed when used for rolling into strip. Cast for electrical use...... 15328 either horizontally or vertically. for other uses. ...-.--.-.-.-... 15694 Cnke.-Refiner shape for rolling into plate, sheet, Ingots and ingot bars .-...... -- . 15694 strip, or shape. Aeetangular in cross section of various slzes. Cast either horizontally or vertically, with range (b) High Reaislonce Lake Copper.-minimum purity of weights from 140 to 4000 lb or more. of 99.900 percent, silver and arsenic being counted as Billet.-Refinery shape primarily for tube mandac- copper; resistivity greater than 0.15694 international ture. Circular in cross-section, usually 3 to 10 in. in ohm (meter, gram) at 20' C. diameter and in lengths up to 52 in.; weight from 100 BS-43-Electrolytic-copper wire bars, cakes, .A 1 m lh "V a""" .". slabs, billets, ingots, and ingot bars- Ingot and Ingot BarrRefinery shapes employed for minimum purity 99.900 percent, silver alloy production (not fabrication). being counted as copper. Both used for remelting. Ingots usually weigh from Ruinioity, w. 20 to 35 lb and ingot bars from 50 to 70 lb. Both in~no~bnnl ususlly notched to facilitate breaking- into smaller ohm (meter, pieces. flaml. . Cathode.-Unmelted flat plate produced by eleetro- Wire bars.....-....--..-----.--.. 0. 15328 lytie refinin The customary size is about 3 ft. square Cakes, slabs, and billets: and about jfta K in. thick, weighing up to 280 ibs. for electrical use .--...... 15328 Copper Powder.-Finely divided copper particles for other uses...... --...... 15694 produced by electrodeposition. Ingots and ingot bars...... -. . 15694 PROPERTIES, COMMERCIAL CLASSIFICATIONS, AND USES 15

Blllr43-Electrolytic cathode copper--minimum other combinations in which copper is the chief purity of 99.90 percent, silver being constituent are copper-base alloys. counted as copper. The copper shall have a resistivity not to exceed There are four traditional copper-base alloys, 0.15328 ohms (meter, gram) at 20' C namely, brass, bronze, nickel-silver, and cupro- (annealed). nickel. Nomenclature for many compositions B170-59--Oxygen-free electrolytic copper wire- bars, billets, and cakes-minimum may be confusing under the original concept purity of 99.95 percent, silver being that brasses are copper-zinc alloys and bronzea counted as copper. Resistivity not are principally copper and tin. Modern metal- to exceed 0.15328 ohms (meter, gram) lurgical developments, however, have resulted at 20° C (snncaled). Test samples shall be free from cuprous oxide as in important new alloys and necessitated,re- determined by microscopic eramina- vision and elaboration of many of the ongmal tion at 75 X magnification. Prepared simple definitions. wire aamples, annealed at 800° to 875O C for 20 min in hydrogen, shall withstand four YO0 bends (2 each in Properties opposite directions) without fracture. B72-60--Firerefined casting copper--must con- WROUGHT ALLOYS form to the following requirements as to chemical composition: Brass.-The most widely used and best Copper plus silver mini- known copper-base alloys are the brasses. mum...... Arsenic ...... maximum-- Copper and zinc together form a complete Antimony- ...... -do.. .. series of solid solutions. As zinc is added to Bismuth ...... do .... copper, tensile properties increase, electrical Imn ...... do .... and thermal conductivities decrease, aqd there is some diminishing of corrosion res?stance. Oxygen ...... do .... Brasses are commonlv used in applications Selenium--- -.- - --do-- - - where it is desired td improve some specific Sulfur...... do. ... characteristic of copper while sacrificing only Tellurium ...... do. ... Tin...... do.--- those qualities that are unimportant to the particular application. In general! the brasses B216-4+Fire-reiined copper for wrought prod- offer mechanical properties supenor to those ucts and alloys-must conform to the of copper with some loss in the electrical and following requirements as to chemical thermal conductivities. For certain mill prod- composition: P"& ucts and manufactures, brasses are selected Copper plus silver ...... minimum.- 99. 88 instead of copper because of the lower cost. 012 A%nic.~...... maximum. .. There are two broad classifications , of Antimony ...... do.. ... 003 wrought copper-zinc alloys, one conLaipg Selenium plus tellurium .---..do-. - - . 025 Nick...... do .... .05 64 to 99 ercent copper, consistlog of a smgle Bismuth ...... do,003 phase an1 known as alpha brasses; the other Lead...... do .004 containing 55 to 64 percent copper, containing two phases and known as alpha-beta brasses. COPPER BASE ALLOYS The alloys of copper and zinc containing less than 55 percent copper, owing to predominance Nature of the beta phase, are brittle and of no com- mercial significance. Copper-base alloys comprise a series of alloys Alpha brasses are exceptionally ductile and having at least 40 percent copper with the malleable at room temperature and can be amount of copper not less than that of any cold worked by any of the commercial methods other constituent. Theoretically, adding such as deep drawing, spinning, stamping, another element to w per makes the mixture forming, cold rolling, cold heading, flaring, an alloy, however smafi the addition. But, in and u setting. Their hardness is increased practice, copper is considered commercially by col d' work, the degree of hardness being de- pure if it is not less than 99.88 percent, silver pendent on the amount of cold w-ork and the being counted as copper. When other elements copper content of the alloy. Alpha brasses are included with copper in small enough containing more than 85 percent copper have amounts so that they produce certain desired work-hardening properties similar to those qualities without chan g the basic charac- of copper, and because of this property these teristics of the copper, tr' e result is a modified brasses are used extensively for applications copper with a copper content of neither less requirin successive drawing operations without than 99.3 percent nor more than 99.88 percent, intermekte anneals. After cold-working op- silver again being counted as copper. AU erations, the brasses can he rendered mallea- ble or ductile again by heat treatment at Brass that contains less than 85 percent temperatures ranging from 700' to 1,400' I?, copper may under certain conditions fail by depending upon the properties desired. Alpha stress-corrosion cracking or, as it is more brasses are single-phase alloys; they are not commonly called, season cracking. Conditions susceptible of hardening by heat treatment. promoting this form of failure are the presence Those alpha brasses containing between 64 of internal stress, produced by cold-working and 80 percent copper possess relatively poor operations, and exposure to mild atmospheric hot-working properties. In order to hot roll corrosion. Traces of ammonia in the atmos- or hot forge these alloys successfully the phere accelerate this type of corrosion. Season utmost care must be taken to keep lead, a cracking can be prevented effectively by relief natural impurity of most zinc, to a trace. annealing below the recrystallization tempera- Brasses of this group are best hot worked at ture. temperatures in excess of 1,350" F; the best The following are the more important alpha results are obtained if all hot working is done braases: within the range of 1,350' to 1,550' F. The alpha braases containing 80 percent .or more Name: of copper have hot-working properties com- Gilding metal ...... parable to those of copper, which is extremely plastic through a wide temperature range. Red bra...... 85 15 Lobr ...... XO 20 As in the case of copper, however, care must Cartridge brass ...... 70 30 be exercised to control the lead within very close limits. As a general rule, if these brasses Gilding metal and commercial bronze are do not contain in excess of 0.01 percent lead, extremely easy to cold work, have hot-working they can be hot forged, hot rolled, or otherwise properties comparable to copper and can be hot worked without any dZ~culty. readily spun, drawn, forged, and upset. These In the alpha range, tensile properties increase alloys have slightly higher tensile properties and with increasing zinc wntent, which is also about the same ductility as copper but lower accompanied by a change of color from red thermal and electrical conductivities. through gold to the green yellows and a pro- Red brass and low brass have excellent gressive decline of electrical and thermal corrosion-resisting and cold-working properties, conductivities. frequently being superior to those of copper. The corrosion resistance of alpha brasses is Cartridge brass, yellow brass, and intermediates adversely affected by the same substances and are known generally as the high brasses. These conditions aa those affecting the resistance of alloys possess the optimum combination of copper. In some instances they may be strength and ductility. High brasses all have corroded by substanow, particularly those excellent cold-working properties and can be which might be called active chemical reagents, readily spun, drawn, forged, and upset. that do not affect copper to any appreciable The alpha-beta brasses-that is, those con- extent. An exception to thii generality is that taining from 64 to 55 percent copper-are much in resisting corrosive attack of sulfides the easier to hot work than those in the alpha range, brasses, on the whole, are better than wpper; the ease of hot working increasing as the copper and their superiority in. that respect becomes content decreases. These brasses become in- more marked as the zxnc content increases. creasingly difficult to cold work as the cop er It is of particular interest that in combating content decreases, and those containing l"ess the corrosion of sea water, certain of the than 58 percent copper are unsuited for any brasses-for example, 85-15 brass (known as cold-workiug operations. Like the alpha rich low or red brass)-withstand corrosion brasses, the alpha-beta brasses can be rendered better than copper. soft after cold-working operations by anneaIing Brasses containing less than 85 percent within the temperature ran e from 700' to wpper when exposed to ,certain media fre- 1,400' F, depending upon tfl e properties re- quently fail in a characteristic manner known quired. The alpha-beta brasses, however, can as dezincification. Failures of this kind are be hardened slightly by uenching from the identified by the spongy areas of wpper in the annealing temperature. T1 e hardening is pro- form of layers or so-called plugs on the affected duced b formation of a greater amount of beta surface. This spongy copper results from the in the aioy than would be produced by slower solution of fractions of the alloy in the media cooling. The alpha-beta brasses possess the Pighest and a redeposition of copper by chemical dis- tensile properties and the lowest ductdity of placement. Arsenic, antimony, and phos- any of the copper-zinc alloys. Both -of these phorus are effective dezincification inhibitors properties are dected by the ratio of the beta in alpha brasses. phase to the alpha phase. Alloys of the lowest PROPERTIES, COMMERCIAL CLASSIFICATIONS, AND USES 17 copper content, because of the greater per- divided into two general types, grades A and B. centage of beta phase, are the strongest and Grade A silicon bronzes are those containing the least ductile. The alpha-beta brasses with the maximum of silicon (2.25-3.25 percent) and of higher copper content approach the a1 ha the third constituent and are used in those brasses containing 64 percent copper in duct&y applications requiring the highest tensile prop- and strength. erties in combination with a resistance to Lead is added to brass primarily to improve corrosion equal to or better than that of copper. its machineabiity; it also definitely improves Grade A alloys possess welding characteristics shearing, blanking, and piercing operations. similar to those of the mild steels.. Grade B Lead is virtually insoluble in alloys of copper silicon bronzes contain smaller amounts of and zinc and, when present, occurs as finely silicon (0.9s2.25 percent) and of the third divided and distributed metallic particles. constituent and are characterized by unusually This uniform dispersion throughout a brass good cold-work'mg properties in combination alloy causes the chips to break off, and very with tensile properties comparable to 70-30 little heat is transmitted to the edge of the brass, corrosion resistance similar to that of cutting tool during machining. With leaded copper, and weldability almost equal to that brasses, friction between the chip and the tool of ade A alloys. is reduced to a minimum while, with copper- Euminum bronzes are high-copper 'alloys zinc alloys, the chi s are long and tough, tool containing between 4 and 10 percent aluminum. wear is high, ang lubrication problems are Small amounts of iron. nickel. silicon. and difficult. ~uanganes~sre~frequrntiy added' to the 'dojs The presence of lead in brasses does not of II~L'II~alulninum content lo u~crcasestrenrrth appreciably influence the mechanical strength and kardness. Industrial aluminum broGes or corrosion resistance of the parent alloy, but are of two general types: The alpha or single it drastically reduces the ease of flaring, up- phase alloys-often referred to as homogeneous setting, cold heading, and bending operations. alloys; and the alpha-beta or two-phase alloys- Lead in alpha brasses renders them hot-short known eommercidly as duplex bronzes. Under and unsuitable for fabricating by hot-working equilibrium conditions, 9.8 percent of aluminum methods. The alphebeta brasses containing is soluble in copper bafore the beta phase between 55 and 60 percent copper can be hot appears, but in commercial practice equilib- rolled if the lead does not exceed 1 percent and rium conditions are practically never reached, can be successfully hot forged with up to 2 and alloys containmg more than 7.5 percent percent lead. If greater amounts of lead are alumhum usually exhibit two phases. present, cracking in forging may occur. As the The alpha aluminum bronzes possess excel- copper content increases beyond 60 percent, lent cold-working properties. They also have less lead can be tolerated. When the limit of good hot-working properties and can be readily the beta phase is reached, between 63 and 64 hot forged, rolled, and extruded. They are percent copper, lead must be kept to a trace if most plastic within a temperature range ,of hot-working properties are to be retained. 1,450" to 1,650' F. Their hot plasticity m- Bronze.-Tin is the essential alloying element creases as the aluminum content increases and, in the phosphor bronze group of alloys. The conversely, their cold-working properties de- maximum limit for tin is about 10 percent in crease with a corresponding increase in sensi- alloys that are to be cold worked, and up to tivity to work hardening. The annealmg this amount the copper-tin alloys are of alpha characteristics are similar to those of the alpha grain structure. Addition of tin to copper brasses, and softening of work-hardened alloys Increases the strength and hardness at a rapid can be accomplished by annealing between rate and reduces the melting point, density, and 800' and 1,400' F, depending upon the electrical and thermal conductivities. Tin is properties required. added to some of the brasses in amounts of The duplex (two-phase, alpha-beta) alumi- about 1 percent for improving resistance to num bronzes have excellent hot-working prop- corrosion by dezincification in sea water, as in erties through a much wider range than the admiralty brass, naval brass, and manganese alpha bronzes. They can be extruded and hot bronze. Tin is particularly beneficial in pro- forged into very intricate shapes. Their hot- viding the high-elastic limit, resilience, and working properties compare favorably with endurance strength characteristics of springs those of the alpha-beta brasses but they can made from phosphor bronze. be cold worked only lightly. The copper-silicon alloys or silicon bronzes All aluminum bronzes possess ood resistance are essentially alloy' of copper and silicon to scaling or oxidation at elevatef temperatures, containing a third constituent usually from 0.25 being better in this respect than any of the to 1.25 percent of one of four elements-tin, other copper-base alloys. The resistance to manganese, zinc, or iron. These alloys are scaliig or oxidation increases with the alumi- num content. The corrosion resistance of Arsenic is added to the extent of a few these alloys is due to formation of aluminum hundredths of a percent as an mhibitor of oxide (AI1O3) on exposed surfaces. This film dezincification corrosion in admiralty and is very resistant to attack by mineral acids, aluminum brass. but it is soluble in alkalies. Thus, aluminum Cadmium in amounts to 1 percent is added to bronzes have been widely used in ?id en- copper to increase strength and wearing quali- vironments, but offer only moderate resistance ties with less sacrifice of electrical conductivity to the att,ack of strong alkalies. In general than when other alloying elements are u~d the wrought, aluminum bronzes are selected to obtain the same strength. This c?mbinat~on for those applications, requiring high-teusde of properties makes cop er-cadmium alloys properties, good corrosion resistance, strength, especially sultable for troS ey ~s,. long-span and wear-resisting qualities. power lines, and similar apphcatlons. Cupronicke1s.-Nickel 1s the major alloying Beryllium is added to coppw in amounts to element in the cupronickels. The most evident about 2 percent to obtam preci itation- effect is the change in color of the alloy as the hardening alloys of strength and hardhess far nickel content increases. The color of cupro- beyond an of the other copper alloys. The nickel is almost nickel white. The addition commercia9 copper-beryllium alloys after a 2- of nickel to copper increases the strength, hard- or 3-hour heat-treatment at 1,450 to 1,500° F, ness, and modulus of elasticity,bu!, lowers the followed by a water quench to return the alpha electrical and thermal conduct~v~tlessubstan- structure, are malleable and can' be drawn, tially. Although nickel and copper are stamped, or cold worked. After such working mutually soluble in all proportions in the solid or cold working, and in order to establish state, 30 percent nickel is usually the maximum phase equilibrium with attendant hi h me- content permissable for alloys to be manufac- chanical pro erties, parts are subjectef to an tured with brassmill equipment. At more than aging anue af' at 525' to 575' F for varyin 30 percent nickel the melting points and periods of time, dependent upon the physicaK annealing temperatures reach values that are dimensions of, the part and the properties too hi h for the furnaces, and the resistance required. It 1s common ractice to add a to col f work becomes too great for customary third constituent; cobalt is Prequently added to brashid reduction schedules. Cupronickels obtain high-temperature stabil,ity, and nlckel are ~articularlvsuitable for service at elevated is introduced as a minor constituent to retard temperatures. " grain growth. Minor Additions.-Maneanese is added to some of the wrought copper alloys, principally CASTING ALLOYS as a minor or secondary alloying element. In manganese, aluminum, and silicon bronzes, it The properties of brass and,bronze castings improves the grain structure. In cupronickels are dependent on the wmposltlou of the alloy, and nickel-silvers, small amounts are added to the cleanlines of the metal, and the methods of improve the metal quality of mill shapes for casting. The properties may ,vary, as the working operations where its presence is percentages of the major constituents aSe at permitted in the finished products. or near the mini or maxlmum lmuts Phosphorus is confined almost entirely to the permitted in the specifications for the alloy. phosphor-bronzes, where it is present in amounts They ma be affected because of the tolerance to 0.50 percent. It serves as a dwxidizer, and specified 9or other elements. The techniques of the residual phosphorus content increases the sand casting, permanent-mold casting, die mechanical properties. In admiralty and alu- casting, investment casting, plaster-mold cast- minum brass, phosphorus is used as one of the ing, centrifugal castings, and othef methods inhibiton of dezincification. It reduces elec- may account for variations found m castlngs trical conductivity substantially, but when of the same alloy. Test bars cut from a casting used in combination with a small amount of produced by one method can have different nickel to form nickel phosphide, the phosphide properties from those obtained from a casting can be precipitated by heat treatment to produced by another method. increase strength, and because it is not in solid Strength, ductility, hardness, etc., are subject solution, the phosphorus ceases to affect to variation due to grain size. In general, conductivity appreciably. the coarser the grain the lower will be the Iron used as a minor alloying element in tensile strength, elongation, reduction in area, manganese, aluminum, and silicon bronzes adds hardness, and impact strength. Grain size is strength and makes a her-grained alloy. dependent chiefly upon the rate of cooling of Small amounts added to cupronickels improve the casting, which is influenced by many resistance to corrosion by sea water. variables. .PROPERTIES, COMMERCIAL CLASSIFICATIONS, AND USES 19 Commercial Classification Cupronicke1s.-Essentially, these are copper and nickel, the nickel content usually being 10, Copper-base alloys are grouped in two classes 20, or 30 percent. Small amounts of iron and according to specifications required in the manganese may be and usually are added. processes of fabrication. These two classes are Special Alloys.-There are many special and wrought alloys and casting or foundry alloys. proprietary alloys that are essentially defmed by their names; included are aluminum-tin WROUGHT ALLOYS bronze, aluminum4licon bronze, cadmium. These are made by alloying the various com- bronze, chmmium copper, beryllium copper, ponents and casting the alloy into slabs, cakes, leaded copper, selenium copper, and others. or bidets for hot or cold working by rolling, drawing, extrusion, or forging. Depending on CASTING ALLOYS the alloy, the wrought products comprise such Mostly brasses and bronzes, these are made diverse shapes as plate, sheet, strip, bar, rod, essentially from a complex assortment of in- wire, and seamless tube. The chief elements dustrial nonferrous scrap by scientific selec- alloyed with copper are zinc, tin, lead, nickel, tion, smelting, and refining processes for sand silicon, and aluminum and to a lesser extent, and ermanent-mold castmy. The quantities manganese, cadmium, iron, phosphorus, arsenic, of alloying metals, such as ead, tm, iron, and chromium, beryllium, selenium, and tellurium. aluminum are usually greater than in wrought The range of chemical compositions for the alloys and are a necessary part of the composi- wrought alloys of copper is narrower than for tion. Elements present as impurities are casting alloys. Many compositions that can greater in amount than they are in wrought be poured successfully into either sand or metals but are not considered harmful within permanent molds are entirely unlit for working the limits of the specifications. Casting alloys operations. In rolling, drawing, forging, extru- are produced by fums known as ingot makers sion, or tube-billet piercing, a high degree of or manufacturers, and most all casting alloys ductility or malleabiity, either hot or cold, is a are marketed and consumed in ingot form. In prime requisite. Compositions of wrought 1945, the American Society for Testing Ma- alloys referred to as standard in the copper- and terials adopted a standard classification of dif- brass-mill products industry are shown in ferent types of cast copper-base alloys. There table 2. are many hundreds of these alloys, and the Brass.-This is any copper-base alloy con- classification simplifies the terminolo taining zinc as the principal alloying component, various types; each class shown genera$ 1y Ofcovers the with or without smaller quantities of other many alloys. This classification bearing the elements. There are allow that are definitely ASTM designation B11945 and endorsed by brasses by definition, yet the have names thai the American Foundrymen's Association is include the word bronze; 9or example, com- reproduced here as table 3. mercial bronze (90 percent Cu-10 percent Zn). Although it is recognized that these alloys tech- nically are not bronzes, they do resemble bronze USES OF COPPER AND COPPER-BASE in appearance and, because of long usage, terms ALLOYS such as "commercial bronze" have wides~read- acceptance. The use of copper and its alloys is un/versal. Bronze.-This is a copper-base alloy having They are practically synonymous with all tin as the principal alloying constituent. How- things electrical and have a myriad of uses in ever. the term "bronze" is seldom used alone construction, autos, aircraft, missiles, railroad and'the copper-tin alloys have come to be equipment, marine equipment, appliances, ma- known as phosphor bronze because of the small chinery and equipment, scientific mstruments, residual phosphorus content. With a suitable utensils, jeweb, cladding, and many other modifier use of the term "bronze" also extends applications. to a variety of copper-base alloy systems, hav- Ap roximately half of all copper consumed is ing the principal alloying element other than for 3ectrical applications, includ@g poyer tin or zinc. These systems include the alumi- transmission, electronics, and electncal equip- num bronzes, the beryllium bronzes, and the ment, trans ortation, and complex weapons silicon bronzes. s stems. ~gegreatest use is for construction Nickel-Silver.-Formerly known ss German (Iomes, plants, office buildings) ,and power silver, this is a copper alloy containing both generation and transmission. Virtually ,all nickel and zinc. Its name derives from its building wiring is cop er The transmission predominantly silvery color. Depending on the of power continues to fe8 major market for composition, the color may vary from yellowish copper, even though aluminum is now used fpr white to silvery white. " most high-voltage overhead lines; copper stdl 20 COPPrn

TABLE2.-Composition. and forms of wrovght copperhe aUoys I Nominal composition, percent I Name Other Typical forms 1 Zinc Lead Tin 1 El* 4 ment cent - -per- I Brasses-nonleaded: Guilding, 95 percent ...... - -. Commercial bronee, 90 percent...... -. Red brass, 85 percent ...... Low brass, 80 percent...... - -. Cartridge brass, 70 percent ...... Yellow brass, 66 percent ...... Yellow brass, 63 percent ...... - -. Muntz metal...... Leaded brasses: Leaded commercial bmnae ...... - -. Leadedtube brass ...... High-leaded tube braas ...... - -. Low-leaded brass ...... -. Medium-leaded braes ...... High-leaded brass ...... - -. Free-cutting brass ...... - -. Leaded munte metal ...... -. . r. Free-cutting munte metal ...... T. Forgjng brasa ...... - -.. RF. Architectural bronze...... - -...... EB. Tin and aluminum brasses: Inhibited admiralty a-...... - -.. P,T. Naval brw...... P,S,R,W,T,F. Leaded naval braas ...... -. .- RF. 0. 30 P,R,F. Manganesebronee ...... 1. 00 Aluminum bms 1...... 2 00 T. Phosphor bronze: Phosphor bronze ...... 25 S,R,W,T. Do ...... 25 S,R,W. Do...... Do...... 25 S,R,W. Do...... 05 9. Med...... lo 9,R. Freecutting ...... 10 R. Cupmnickels: Ila 00 P.T. 1. 25 . 40 10. 00 P,R,T. Do...... 60 .50 Nickel-ailvera: Nickel silver-- ...... I Do...... Do...... Do ...... Silicon bronzes (Coppersilicon alloys) :

High-silicon bronze ...... 1

Low-silicon bmnae ...... 1 Aluminum bronzes: Aluminum bronze ...... Do.-...... Do......

Aluminnmsilicon bmnze ...... See footnotes at end of table. PROPERTIES, COMMERCIAL CLASSIFICATIONS, AND USE8 21 TABLE2;--Compo8ition andform of wrought eopper-bcsse days--Continued I Nominal composition, percent I Name I I I I I Other I T~oical forms ' Copper Zinc Lead Tin Ele- Per------ment cent Other copper alloys: I Cadmium bronze ...... 99.00 ...... Cd 1. 00 W...... Cr .85 R. Chromium copper 99.14 { Si .01 Beryllium copper- ...... 4 97.70 ...... Be 1.90 S,R,W. Leaded copper ...... 99.00 ...... Pb 1.00 R. &lenium copper ...... 99.40 ...... Se .60 R.

Source: Butts, Allison B. Copper, The Metal, Its Alloys, and Compounds. Reinhold Pub. Corp,, 1954, p. 537.

Addition elementa I Remarks copper I copper. ------. Not more than 2 percent total of arsenic, Conductivity copper castings, pure copper, zinc, cadmium, silicon, chromium, sil- deoxidized copper, and slightly alloyed ver, or otherelements.

Red. -..- .- - - .- .- - -.- - . 2 to 8 Dercent rinc. Tin less thanzinc. Alloys in this chwithout lead seldom Leadiess than 0.5 percent. uid in foundry work. Leaded red ...... 2 to 8 percent zinc. Tin leas than 6 Commonly used foundry alloys. May be percent, usually leas than zinc. Lead further modified by addition of nickel. than more 0.5 .--~-oeromt.~ See ASTM Soeoifications B62 and B145. Semired-...... 8 to 17 percent sinc. Tin less than 6 MOTSin this class without lead seldom percent. Lead less than 0.5 percent. uid in foundry work. Leaded dred.- ...... 8 to 17 percent ainc. Tin less than 6 Commonly used foundry alloys. May be percent. Lead over 0.5 percent. further modified by addition of nickel. See ASTM Smification B145. Yellow ...-----...... More than 17 percent sinc. Tin less than Commonly used foundry alloy. 6 percent. Lees than 2 percent total aluminum, manganese, nickel, iron, or silicon. Lend Leas than 0.5 percent. Leaded yellow. ------. More than 17 percent zinc. Tin leas Commonly used foundry alloy. See than 6 percent. Less than 2 percent ASTM Specification B146. Fal aluminum, manganese, nickel, or Iron. Lead more than 0.5 peroent. High-Btrength yellow, More than 17 percent zinc. More than Commonly used foundry allow under manganese bronze. 2 percent total of aluminum, manga- name of "manganese bronze" and nese, tin, nickel, and iron. Silimn various trade names. See ASTM Spec- less than 0.5 . Leadless than ification B147. 0.5 percent. FtIn less than 6 rcent. Leaded hi h rength More than 17 percent zinc. i&e than Commonly used foundry alloys. See yellow, fea 2 ed manga- 2 percent total of aluminum, manga- ASTM Specifications B132 and B147. nese bronze. nese, tin, nickel, and iron. Lead more than 0.5 percent. Tin lesa than 6 percent. Silicon...... More than 0.5 percent silicon. More Commonly used foundry alloys. See than 5 percent rinc. ASTM Specification B198. 7BSrrU) + TABLE3.-Cast copper-base alloyeContinued

Addition elements Remarks

Brasse4ontinued

Tin--.-...-...------More than 6 percent tin. Zinc more Alloys in this class seldom used in foundry than tin. work. Tin-nickel ... ------More than 6 percent tin. More than 4 AUoys in this class seldom used in foundry percent nickel. Zinc more than tin. work. Nickel, nickel silver.. .. . More than 10 percent sinc. Nickel in Commonly used foundry alloys, some- amounts sufficiint to give white color. times called German silver. Lead less than 0.5 percent. Leaded nickel, leaded More than 10 percent zinc. Nickel in Commonly used foundry alloys, some- nickel-silver. amounts su5cient to give white color. times called "German silver." See Lead more than 0.5 percent. ASTM Specification B149.

Bronm

2 to 20 percent tin. Zinc less than tin. Commonly used foundry alloys. May be Lead less than 0.5 percent. further modilk3 hy addition of some nickel or phosphorus, or both. See ASTM S~mificatiousB22 and B143. To 20 percent tin. Zinc less than tin. Commonly -used foundry alloy*. May be Lead more than 0.5 percent, leas than funher modified by addition of some 6 percent. nickel ur phosphorus, or both. See ASTM Srrcifications B61 and 8143. To 20 percent tin. Zine less than tin. Commonlyused foundry alloys. May be Lead more than 6 percent. further modified by addition of some nickel or phosphorus, or both. See ASTM S~ecifications B22. B66. B67. and B144: Lead more than 30 percent. Zinc leae Used for special bearing applications. than tin. Tin more than 10 percent. More than 10 wment nickel. Zinc less Commonly used foundry alloys. Some- than nickel. Leas than 10 Dement tin. times called German silver or nickel- Leas than 0.5 percent lead. silver. Leaded nickel--.-...--.- More than 10 percent nickel. Zinc leas Commonly used foundry alloys. Some- than nickel. Les than 10 percent tin. times called German silver or nickel- More than 0.5 Dercent lead. silver. See ASTM Specification B149. Aluminum-. - - -... . . -. - Commonly used foundry alloys. Some may cent uon, with or without manganese be heat-treated. May be further modi- or nickel. Less than 0.5 percent fied by addition of some nickel or tin, or silicon. both. See ASTM Specification B148. More than 0.5 percent silicon. Not over Commonly used foundry alloys. Some 5 percent zinc. Not over 98 percent are readily heat-treated. See ASTM copper. Speoification B198. More than 2 percent beryllium or beryl Mast of these alloys are heat treatable. bum plus metals other than copper.

dominates in high-voltage underground lines. The noncorrosive quality of copper and !ts Generation and utilization of electrical energy alloys accounts for many uses in construct~on requires extremely large quantities of copper. for rooling products, plumbing goods, bullders Examples are heat exchangers, windings m hardware, and functional decorative appllca- motors, generators and transformers, magnet tions. Sheet roofing, gutters, downspouts and wire in control apparatus, and bus bars. heads, flashing, fittings, and accessories con- For communications, telephone and telegraph sume a large amount of copper. Cop er and wire and cable are the two greatest +es. red brass are found fre uently in pP umblng . Numerous components in radio and televlslon items such as tank-lever lift arms, todet tank sets and telegraph receiving and sending equip- trim, lavatory fittings, tub fittings, faucets, ment are made of copper or its alloys, and traps and drains, flush valves, plpi and coaxial cables employ a substantial amount of tubing, and other fixtures. Brass and"f ronze copper. The excellent electrical conductivity are popular for builders hardware because they of cop er has made it the major metal used in are decorative, noncorrosive, and easy to expan8. mg applications of printed circuits. fabricate for such items as locks, door knobs PROPERTIES. COMMERCIAL CLASSIFICATIONS, AND USES 23 and hockers, door stops, hinges, bolts, latches, and' heat exchangers use copper or its alloys and safety hasps. in many ways. Specific uses are co per for The automotive industry accounts for about motors, other electrical equipment an8tubing; 9 percent of the copper consumed in the United bronze for worm wheels, oil baffles, check States, using about 30 to 40 pounds per vehicle. valves, and levera; cupronickel for tubing; Volume use is in radiators, heaters and de naval brass, muntz metal, and aluminum frosters, air conditionin units, bearings, bush- bronze for plates, sheets, bars, and weld wire. ings, carburetors, oil &es, stramers, wiring, Copper is used extensively in watches, switches, and plating. Major uses take strip, clocks, microscopes, projectors, and many types tube, plates, and wire; secondary uses take rods, bars, and foundry products. Of Sogap d copper, brass, and bronze are popular More co per is required for the maze of materials in utensils, jewelry, furnishings, and wiring in ef. ectncal systems of airplanes than decorative items. They are used in manu- for any other use m the alrcraft industry. facturing such items as: Brass and bronze Some of the larger planes use as much as 3,000 medallions; solid brass furnishin towel bars, pounds of copper in electrical systems and curtain rods, wall hooks, anf%ap dishes; mechanical components. copper, brass, and bronze jewelry; cookware; Use of copper is minor, though essentig, @ tablewme; and bronze and brass plaques and missiles. As in aircraft, the major use IS m signs. wirin systems. From data contained in the 1958 Census of Ra$, oads use a large quantity of copper in Manufactures by the Bureau of the Census, a diesel locomotives, passenger cars, and switch- table compiled by the Copper Division of ing and si a1 devices. The average Pullman BDSA, U.S. Department of Commerce re car uses 8% ost 2,000 pounds of copper tube produced here in table 4 shows end uses of in the water supply system, air brakes, heating copper and copperbase alloys in the form of system, air conditioning unit, condensers, bare wire, insulated wire and cable, and other evaporator, and heating coils. mill shapes and forms. The percentage of total Tankers, cargo shlps, pleasure craft, passenger metal consumed by vario,us fabricating in- liners, ,and naval vessels use copper and its dustries is of particular interest. The im- alloys m a great variety of marine equipment. ~ortanceof the electrical industrv is amarent. Naval braas is used for propeller shafting k almost 35 percent of total c~&~m~iionw& (because of its strength, torque resistance, accounted for by electncal machmey. Con- macbinability, and co~osionresistance); man- sumption by the military, the automotive ganese bronze for struts and rudders (high industrv. and for refrieeration- eauiument- is strength and corrosion resistance); silicon also ' "&cant. bronze for fastenings and water tanks; soft and fi%ucts of the powder-metallurgy pro- hard drawn copper for exhaust yokes; fuel have found wide usage in machine components. lines, water lines, and pipin (resistance to Comuacted structural parts are used m auto- corrosion and leaks, workab%ty, long life). motiGe, railroad, farm, aircraft, ,marine, and The USN nuclear submarine Skipjack uses brass communications equipment and m household in capstans, torpedo tubes, divmg gear, and a pliances, such as washers, dryers, ironers, valves; more than 48,000 feet of co per tube in eictric fans, and refrigerator?. Metal powder hydraulic, air, and lubricating oiP lines; and of single elements, or in combmation with other more than 6,000 feet of cupronickel tube in metals or nonmetals are processed to make oil- auxiliary cooling lines, heat exchangers, lav- impregnated porous bearings; cams, gears, atories, bilge pumps, and salt water service motor brushes, clutch facmgs; contact pomts, lines. filters, filaments, lock assemblies; and many Manufacturers of appliances such as washing other various shapes. machines, air conditioning units, refrigerators, The number of automotive applications for radio and television sets, and other units powder-metal parts has doubled since 1950. specify copper and its alloys for many com- Chryder Corp. and General Motors Corp. now ponents requiring materials that are electrically use about 100 different powder-metal parts in or thermally conductive, corrosion resistant, their cars; the Ford Co. uses slightly less. Iron and durable. Radio and television sets provide powder mixed with copper, or copper and the largest market for printed circuits, but carbon, is used for transmission and engine there is great potential for their use in appli- parts that receive high impact and fa!lgue ances, automobile instrument panels, and loads. Many new. applications are believed electronic computers. feasible as powders and processing methods Large machinery and equipment, turbines, are designed for strength properties. COPPrn

TABLE4.-End-mes of copper, 1968

B included w hble. Heable. 1 and 1.5 million rmmds of iawlated wk and cable were PROPERTIES, COMMERCIAL CLASSIFICATIONS, AND USES 25 Copper As an Alloying Element percent gold with about equal parts of silver and copper has a yellow color; replacing more In addition to its role in co,pper-base alloys, of the silver with copper produces a red gold. copper is an important constituent of a large The 14-carat alloy of 58.35-percent gold, 2.5 to number of alloys having a metal other than 5 percent copper, and balance of silver is green. copper as the principal component. Increasing the copper to 20 to 30 percent makes Aluminum Alloys.-In 1911, the German yellow golds, and higher copper gives a reddish metallurgist, Wilm, announced development of color. The lo-carat golds are largely high- Duralumin, a series of alloys containeg about copper alloys with various additions to control 4 percent copper, 0.5 percent magnesium, and color. White gold is a series of gold-nickel- 0.5 percent manganese. This development copper-zinc alloys containing the requisite marked the real beginning of wrought aluminum amount of gold to make lo-, 12-, and 14-carat alloys. Pure (99.9" percent) alummum, as alloys. The copper varies from 51.5 to 31.0 cast, has tensile and yield strengths of only percent. 9,000 psi and 3,000 psi, respectively., Addition Nickel-Co per Alloys.-Copper is soluble of copper to and beyond the lim~tof solid in nickel in fm th the liquid and solid states in solubility strengthens aluminum rapidly. all proportions, and all-the alloys have homo- Aluminum will dissolve 5.65 percent of copper genous structures-regardless of the heat treat- at 548' C (1,018" F), the eutectic temperature, ment. Although all of the alloys are ductile, but will hold only 0.45 percent at equilibrium only Monel and constantan have much com- at 300° C (572' F). The hardening effect of mercial utilization. A third alloy, 70 Ni-30 copper added to aluminum is due to age harden- Cu, has a special use in the form of wire or ing or precipitation hardening caused by pre- ribbon for &agnatic tzmperature compensation cipitation of very heparticles of Cud,. The in electrical mvters which depend on the flux precipitation of this compound to form a two- produced by a constant voltsge or by a certain phase structure was found to produce a stronger load current for their .actuation. allov than the- solid solution. while retainine- Monel is the most important nickelapper hig6 ductility. alloy. It is available in both cast and wrought Although the newest wroueht allow contain form. This alloy-67 percent nickel, 30 per- copper, iris no longer the phcipal'hardening cent copper, and the balance iron and man- element. The new alloys are widely used in ganeseis a strong, ductile alloy that can be aircraft construction, but the aluminum-copper- formed into rod, wire, plate, shaft, strip, and base alloys still dominate the light alloy field. tubing. Ingots are cast of this alloy that Ferrous Alloys.--Pure copper and pure iron weigh as much as 14,000 pounds. The tensile are miscible in the liquid phase in all propor- strength varies from 70,000 psi in the annealed tions. Introducing carbon affects the miscibil- state to 120,000 to 140,000 psi in the fd-hard ity, however, so that a molten eutectic iron condition. The mechanical properties are containing 4.3 percent carbon can dissolve only quite stable with tem eratures , to 400° C about 3 ercent copper. Ductile alloys can be (750' F). Monel is wi iely used m chemical, producef throughout the entire co,mposition pharmaceutical, and marine equipment, la?- range, but copper in commercially ~mportant dries, and kitchens because of its pleasmg iron-base alloys is limited to approximately appearance, strength, and resistance to gea 2.5 percent, and is usually lower. About 0.25 water, dilute sulfuric acid, and strong caustics. percent copper in copper-bearing steel will Constantan is an alloy of about 45 percent roughly double the corrosion resistance of the nickel and 55 percent copper that is distin- steel in air. Copper increases the depth of guished by its high electrical resistance and un- hardening after quenching any +eel, but, its usually constant temperatufe coefficient of relative effect is much reater in the hgh- electrical resistivity. Extensive use is made carbon than the low-cargb on steels. In cast of this property in electrical instruments. iron, copper reduced the tendency toward chil- Silver-Copper Alloys.-The silver-copper sys- ing in light sections and at the same time tem is relatively simple, with a eutechc at 28.1 promoted soundness in heavy sections. In ad- percent copper which solidifies at 779.4;. C dition, copper in cast iron tends to increase (1,435" F). The maximum solid solub~lity strength, improve machinability, and improve of copper in silver at this temperature is 8:8 resistance to wear, galling, impact, and shock. percent, decreasing to about 0.1 percent, m Gold-Copper-Silver Alloys.-Copper hardens e uilibrium at room temperature. The hlgh- gold principally by forming solid solutions. slver, silver-copper alloys can be age hardened. Other elements are added to impart certain They have besn considered to be the classical properties or characteristics. The gold-copper- silver d0ys are more commonly used than 2 ~~thrmghmore than M percent mpwr. constantan is llsted the Netw3-lr d~t~dsrdrmdby the American ol Metslsss gold-copper alloys. An l&carat alloy of 75- ..bm.bsaeay. 26 COPPER examples of age hardening by precipitation of Copper is added to manganese alloys in finely divided particles with simultaneous amounts from 3.5 to 35 percept to increase changes in physical properties. AU of the alloys elongation. The silver-copper-zinc alloys in of silver and copper are ductile. Of the high- which the copper ranges from 0 to 40 percent silver alloys, the most important is the 92.5 are widely used as silver solders. silver-7.5 copper alloy known as sterling silver. The properties of several binary and more The alloy is universally prized for making complex alloy systems based on copper have flatware and objects of art. It can be hardened beep investigated. Studies were made. of the with a considerable gain in yield strength. precipitation hardening of copper containing Another important alloy is 90 silver-10 copper, 2.2 and 4.5 percent cobalt, with and without or coin silver. It is used for silver coinage in the adding 6 to 12 percent manganese. Precipi- United States and for electrical contacts when tation hardening is greater in the alloys con- a harder material than pure silver is desired. tainmg manganese. The eutectic silver-copper alloy (28 percent Cu) is used to some extent as a brazing metal. Copper-titanium and copper-zirconium alloys Platinum-Copper and Palladium-Copper Al- were. investigated by Dies, who reported that loys.-Both platinum and palladium form an alloy containmg 0.25 percent zirconium continuous series of solid solutions with copper. retained work-hardness at moderately elevated Although the do s are potentially useful, temperatures better than the conventional little actual deman d? exists for the binary alloys. silver-bearing copper and had high-electrical The 60 palladium-40 percent copper alloy has conductivity. Copper alloys cont~ining as some use as electrical contacts. Ths ternary much as 2 percent titanium with 0.3 to 1.2 palladiumdver copper alloys with more than percent aluminum were found by (iruhl and 5 percent copper and not more than 65 percent Cordier to give considerable response to pre- palladium are age hardenable and are used in cipitation hardening, together with compara- dentistry. tively high ductility and good workabibity, Ziic-Co per Alloys.-The binary high-zinc, both hot and cold. Zn-Cu alP op are of no great importance A Japanese patent covers a dental alloy of commercially. More important are the ternary golden color containing 51 to 60 percent copper, zinc-copper-aluminum diecasting alloys that 35 to 43 percent zinc, 0.3 to 2 percent silicon, are so widely used in the automotive, electrical and 0.5 to 5 percent of either iron or cobalt. and other industries, The tendency toward Another patented material for special appli- expansion is an important property of these cations-namely, for control rods in nuclear alloys, causing them to fill molds completely. reacto~onsistsof copper containing 5 to 20 Other Alloys.-The high-tin, ternary tin- percent boron and 25 to 79 percent nickel or antimony-copper alloys include all of the high- chromium. tin babbitt metals. The fatigue stre the indentation hardness of these %:sag! crease with increasing anti~onyand copper. Copper Compounds However, the maximum resLstance to crack- ing in sermce is obtained with about 3 to Of the many known copper compounds only 7 percent antimony and 2 to 4 percent a few are manufactured industrially and used copper. The bond strength of babbitt metals on a large scale. In point of tonnage, copper cast on steel decreases as the copper content is sulfate (CuSO,) is the most important to increased from 3% to 7 percent. It has been industry. Anhydrous copper sulfate is a white shown that the decreased bond strength is crystalline substance, but the usual commercial associated with precipitation of Cu,Snb at the form is the pentahydrate (CuS04.5H20),called interface of the babbitt and the steel, where blue vitriol, which contains about 26 percent the compound concentrates during freezing by copper. It is highly valued as a fungicide and normal segregation. Tin-lead-antimony-cop- as a source of minerals for plant and animal per doys are also used for bearings, but are life. Copper sulfate is used extensively to considered inferior to the high-tin alloys. activate sphalerite and other sulfide minerals Lead-base bearing alloys often contain copper in metallurgical flotation, as a print toner in ranging from 0.2 to 7.4 percent. Pewter may also contain a little copper as a hardener. photography, in dyes, galvanic cells, and Copper in amounts up to 4.7 percent may be antiseptics, and as the raw material for pro- used in type metals. The zinc-tin bearing ducing the complex copper ammonium com- metals, britsnnia metal, and various white cast- pound necessary for making crayon. Other ing alloys usually contain from 2 to 11 percent copper compounds and their uses are given in copper. table 5. PROPERTIES, COMMERCIAL CLASSIFICATIONS, AND USES 27

TABLE5.-Copper mmpou~and their wes

Name Formula 2rystal do Soluble in- Typical we8 - Bssic cupric acetate-. Cu(C~H~03.Cu0. Blue ..-... Water, ammonium, Catalyst for making or- 6Hn0. hydroxide acid. ganic compounds. Basic cupric csrhonak CuCOvCu(OH),.... Dark green Slightly in water and Raw material for pmduc- acid. tion of other cnpper compounds, pigment? for paints and cemmcs, fungicides, pyro- technics. Bordeaux mixture.. .. Blue..---. Water, ammonium hy- Fungicide. droxide, acid. Cupmus chloride-- --. White -.... Hydrochloric acid, Catalyst in chemical ammonium hv- manufacturina. con-

Cupmus cyanide. .--. White----. Hydrochloric acid, ammonium hy- droxide. Cupric chloride...... Yellow Water, alcohol, am- brown. monium chloride.

Cupric nitrate .-.-... Blue --.... Water, alcohol .--....

Cuprous oxide .-.-... Dark red.. Hydrochloric acid- - -.

Cupric oxide -...... Brownish Acids --.....-.---... black. COPPER BIBLIOGRAPHY

Anaconda American Brass Co. Cu-401 )per Metals of Copper. John Wiley & Sons Inc., New York, bv bnaconda Pub. B40. 1961. 199 on. 1942 518 pp. BU& Allison. Copper, The &fetal *its AUoys and The 6rganization For European Economics Co- Com ounds. Am. Chem. Soc. donograph Seriea, operation. Powder Metallurgy. Psris, France, ~eingoldPub. Corp., New York, 1954, 936 p 1955, 309 pp. Co per & Brass Bulletins. Copper & Brass kearch Steel. Copper and Its Alloys. V. 143, No. 17, Oct. ksociation quart. pub. 1960-1961. 27, 1958, pp. 75-90. CO per & Brass Research Association. Copper- U.S. Department of Commerce. Uses of Coppe- $he Corneratone of Civilieation. 1959, 33 pp. 1952. Pt. 1-Brass Mill Pmducts, 17 pp.; pt. 2- Iron Age. Copper: Good on All Counts. V. 182 Copper Win Mill Products, 10 pp.; pt. 3-Brass No. 24, Dec. 11, 1958, pp. 126-129. and Bronee Foundry Products, 10 pp., Business Kemecott Cop er Corp., AU About Kennecott and Defense Sew. Admin., 1955. The Story & Kennecott Copper Corporation. Wilkins, R. A,, and E. S. Bum. Cop er and Copper 1961, 31 pp. Base Alloys. McGraw-Hill Book eo., New York Newton, Joseph, and Curtis L. Wilson. Metallurgy and London, 1943, 355 pp. CHAPTER 2-HISTORY PRWSTORY AND EARLY HISTORY The most important copper-ore deposits were OF COPPER in Sinsi, Syria, Baluchistan and Afghanistan, Caucasia and Transcaucasia, the Taurus region, The industrial history of mankind is divisible Cyprus, Macedonia, Iberia, and Central Eu- into two major epochs-a stone age and a metal rope. The co er in use among the Sumerians age. Between these two epochs there was a of southern B' esopotamia (3500-3000 B.C.) transition period, when metals were found in was obtained from Asia Minor which was also their native state and fashioned by hammerin the source for supplying the kssyrians much into useful implements including weapons an ! later. The peaks of production in this region objects of art. Gold and silver were of no in- fell between 2400-2000 B.C. and 1500-1200 dustrial value to rimitive man, and the use of B.C. copper became tBe link between the ages of Copper was worked in Egypt beginning from stone and metal. Copper was the second metal Dynasty I11 (2600 B.C.). It is estimated that used by man, gold being the first. The oldest about 10,000 tons was produced over 1 500 known relics of co per are not necessarily the ears. Some copper mines were in the Arahan first that were ma ie, but hammered copper is %esert, but by far the eatest quantity of found among Chaldean remains that go back copper came from mines oythe Sinai peninsula. to 4500 B.C.; and in the Badariau graves of Although these mines were firat worked for Fayoum in Egypt there is native copper that turquoise, remains of crucibles, slag, and copper may be even more ancient. Some writers be- objects prove that smelting of ore was ractlced lieve that two millenniums separated the first in predynastic times. Production at tg e oldest use of hammered co per from the beginning of mines in Wadi Maghara continued (with a true metal culture, a'i out 3500 B.C., when cop- break between Dynasties V and XI) to 1750 per was smelted from its ores and cast in a B.C. From 1600 B.C. onwards, mlning was mold. This dates the firat lmowledge of concentrated in the neighboring rqon of Jabal cop er at about 6000 B.C. Serabit al Khadim, until it ceased about 'IPhe prehistory and early history of copper is 1200 B.C. when Egypt had wme to depend traced through archeological, philological, tech- upon imports from Cyprus and Armenia. nical, historical, and classical writings concern- Another im ortant copper-mining center was ing the role of copper in changing and advanc- in the WSdi af' 'Arab between the Dead Sea and ing civilizations. The sequence of cultural the Gulf of Aqaba. Here mines were worked development as divided into the well-defined from the early to the middle bronze age, and neolithic, copper, bronze, and iron ages is not again between 1800 and 1300 B.C. by ,the confirmed by the study of the early use of the Edomites. Mining was by the room-and-pdar metals. Such a progression was probably true method; some of the pillars still show thin over diierent spans of time in the ancient Near veins of ore. Tn Cvnrus rnnner.------mminm~ becan about 2500 East, Egypt, and parts of prehistoric Europe, ,C; -B-. -. - : but a definite and uniform succession of metal 0th omde and sdde gres found here cultures all over the world cannot be substan- were used in supplying Egypt during Dynasty tiated. The North and South American In- XVIII (1580-1350 B.C.). The mmes were dians had not entered the metal age until many o erated successively under the dominion of centuries after the Epyptians, and as themineral t %e Egyptians, Assyrians, Phoenicians, Greeks, resources of North America 'elded no tin, there Persians and Romans. The Enelish word. copper, was derived from the reekn name oft& was no bronze age there. Jlouthern India and southern and central Africa also skipped the island of Cyprus, Kypros, through the Latin bronze period. Australia, New Zealand, Japan, cuprum. The same deposit is still being ex- and the islands of the Pacific passed directly ploited, supplying 39,000 tons of copper m 1-""-. afin from the use of stone to that of iron. Copper was used in Chma as early as 2500 B.C., according to the Shu Ching epics,, but Mining no mention is made of the source or the mmmp.- of this copper. Little is known about ancient copper mining In Europe, co per mines belonging to the although it is certain that both open-pit and bronze age are l% own in Austria, Germany, underground mining was practiced in antiquity. France, Spain, Portugal, Greece, and Tirol. 30 COPPER In Ti01 the mines of Mitterberg seem to have Western Asia and North Africa by the fourth been worked from about 1600 B.C. in the millennium before Christ. bronze age to the Hallstatt period of the iron Reducing oxide ores and melting copper is age, about 800 B.C. Probably the most linked with development of the pottery kiln. importsnt cop er deposits in Europe were those It is believed that only a cwilization that made of Spain anB Portugal, includimg the out- well-baked potter requiring a high-baking standing Rio Tinto ore body which is still temperature woul Bpossess the technical equi being exploited. In Britain copper deposits ment that made the reduction of ores possibg found in Anglesey, Cornwall, Devon, and With the knowledge of melting copper came Shropshire are of historical interest, having the new way of fashioning metal objects by been developed by the Romans after the casting. This art also required a knowledge great invasion of A.D. 43. and ability to manufacture crucibles, tongs, and In North America evidence, discovered by means of developing blast air (bloyipe, archeologists in pits found on the Upper bellows). Archeological studies find that 0th Peninsula of Michigan and on Isle Royale in stages had been reached in Near Eastern Lake Superior, reveals that wpper mining and The date of discovery is roughly the forming and use of coppe: implements aqd %i%%~about 4000-3500 B.C. weapons was carried on dunng a prehistoric The last ~hape,reduction, of sulfide ores, period extending from about 5000 to 1000 certainly fa m historic times, though its B.C. There are many of these pits in the exact beginning is still obscure. The two area, estimates of those on Isle Royale alone sta es of roasting th: sulfide ores, then smelting are into the thousands. A section of charred wit% charcoal, in ddferent types of furnaces, log found in one pit and subjected to carbon- each suited to one of the stages, was known dating methods was determined to be 3,000 to the ancient metallurgists. Finds of such years old, plus or minus 350 years; another specialized furnaces and lumps of semirefined piece from the same pit was tested and found and pure copper both m the Near East and to be 3,800 years old, plus or mmus 500 years. such European metallurgical centers as Mltter- When copper was first mined in Central berg prove this. The working of pyrites is Africa is not known. Early Portuguese ex- connected with the invention of bellows, lorers noted pfoduction of copper and iron which is dated around 1580 B.C. Lorn Katanga m their 18th-century reports. Several of the Rhodesian copper belt and Katanga ore bodies had been mined extensively Bronze and mining operations had ceased long before the Europeans anived. These ancient copper Use of bronze dates from remote antiquity. workings and outcrops pointed out by the Its first use was probably for celts and dagger Africans undoubtedly led to extensive ex- blades of the second city of Troy, about ploration campaigns which resulted in develop- 2500 B.C. It was known in Crete around ment of the presently known copper deposits. 2000 B.C. and by the late Aegean civilization between 1600 and 1000 B.C. Significant styles of utensils, weapons, implements, tools, Metallurgy and engraved ornaments whlch have been found reflect the levels of art development m Copper metallurgy started when primitive particular areas in certain periods. Wlth the man discovered that certain stones after bein invention of hollow casting about the mlddle hammered looked like old This new natur3 of the 6th century before Christ bronze became material was worked "by the same procwes the most important material of monumental used when working bone, stone,,or fibers- sculpture. The advancement of the art of hammering, cutting, bending, gvdm , and working bronze throughout the Hellenistic, polishing. This is considered the mtro Cf uctory Roman, Byzantine, and Medieval periods is phase to copper metallurgy. reflected in bronze statuary, furniture, church Annealing native copper was the initial doors, and other ornamental and useful ,articles phase of true metallurgy. When it was found made in those times and still ih elostence. that copper when hot was much more malleable Bell foundbg, an important industry in northern and easy to shape, tempering or annealing Europe, France, Germany, En land, and the followed by hammering became common prac- Netherlands, began in the earf y part of the tice. Brittle forms of native copper which had Middle Ages. resisted shaping could be worked with good results after heating. This digcovery must Brass have been made around 5000 B.C., for the technique was common knowledge of the The mention of braes in the Bible and by peasant culture that had spread over South- Homer, Hesiod, Aristotle, and others un- doubtedly refers to copper or bronze, because abandoned. More extensive operations were brass was not known as such in ancient times. carried on at Sisbwy. The oldest mining Some references claim that brass w,w known to charter in the country was given in 1709 to the the Romans and possibly to earlier cultures, company that worked this mine. For 30 yem indicating that brass may have been produced after 1707 these operatotors were actively en- by the smelting of cupriferous zinc-ores which gaged. They reported that $15,000 had been could have come from mmes in Laurium, expended b them The legislature passed sev- Sardmia, and Cyprus. eral bills &igned to encourage the workers. Brass was produced in the Lpw Countries But since the laws of England forbade smelting beginning about A.D. 300 and it became an the ore here, the product of the mine was important article of commerce. This brass was shipped to England, many consignments being made by the calamine process in which copper made. Small amounts were smelted here, not- shots were heated mth calamine and charcod. withstanding the prohibition. After 1737, the In 1781 James Emerson patented the process returns not being satisfactory, the energ of for producing brass from copper and zinc metals. the operators flagged. The deposit has teen However, brass was produced by the calamine worked but intermittently since. In 1760 a method as late as 1850. company was formed in England to procure copper from the Slmsbwy me. Two ship loads of ore were sent from New York. One of GROWTH OF INDUSTRY IN UNITED these was captured by the French; the other STATES sank in the English channel. This ended for- eign interest in the deposit. Later, for a short The greatest use of copper developed from the time in 1837 and again in 1857 operations were phenomenon of transmitting electricity and the carried on. invention and progressive improvement of the It was not until exploitation of rich ore de- electric generator. In 1831 Michael Faraday posits of the Northern Peninsula .of Michigan discovered that an electromotive force (voltage) in the early 1850's that production in the United is set up in a conducting wire when it is moved States exceeded a few huqdred tons a year. at right angles to or across a magnetic field. Thereafter, smelter production increased from With this principle he developed the dish 728 tons in 1850 to 8,064 in 1860, 14,112 in dynamo or electric generator. Development of 1870, and 30,240 in 1880. In the early 1880Js, the electrical industry was dependent upon US. industry was dominated by Calumet & parallel development of other industries, one of Hecla Mining Co. in Michigan, which was the major ones being the copper industry, which producing half of the domestic output at a cost provided copper wire for transmitting elec- er pound that would be compeiitive today, tricity and for component parts of generators gecause ore ran as high as 20 percent copper. and motors. All the Michi an copper, known as Lake copper, Invention of the telegraph by Samuel F. B. was markete8 by Calumet & Hecla through a Morse in 1840 was the beginning of the first pooling agreement, and the preeminence of public service of electricity. In 1850 the first Michigan was considered unassailable, international cable was laid between Dover, larly by those who financed the Lake rrticu-evelop England, and Calais, France. Alexander Gra- ment. - ham Bell demonstrated the ~rinci~leof the elec- The first discovery of copper in Montana was tric speaking telephone in June i875. Edion in the Parrot mine at Butte in August 1866, a plied for the first incandescent lamp patent but throughout the seventies the Butte mmes 8ovember 4, 1879. Many such inventions and were exploited only for their silver output and discoveries were made--all involving electricity their silver possibilities. The area became and requiring copper for its transmission. famous for copper production when mining of The electrical industry began to receive pub- copper ore began at the Anaconda mine in the lic attention in 1885, and the many develop- early 1880's. Later, the Anaconda Copper ments responsible for its progress until 1905 Mining Company gained control of most of the were made possible b expansion of copper pro- properties in the Butte area because of its duction in the ~nite8~tates. afEliation with Amalgamated Copper Com any Copper was htproduced in the Colonies in Another great copper area was slowly g.eing . 1709 at Sibury, Conn. In 1705 a vein of exploited in the Southwest at the same time. copper ore was discovered in Simsbury. In Development of the oxidized silver-copper ores 1712 another vein was ex osed in what is now of Arizona was financed by the New York Cheshire. Other undertakgs were carried on metal traders, Phelps Dodge & Co. Thus the for a short time in Eaat Hartford, Bristol, and Bisbee operation was first acqured by Phelps other points. At Cheshire the paying ore lay Dodge and in 1885 was merged with the Cqpper only in small pockets and the shafts were soon Queen mine, forming the basis for great mmng 32 COPPER operations in Arizona. In addition, the Bing- of the chief Butte veins. In 1906 Heinze was ham, Utah, property was brought into opere bought out by Amalgamated for 10.5 million tion by 1907, by Utah Copper Co., which was dollars; and Amalgamated, in an effort to later taken over by Kennecott Copper Corp. recoup, curtailed production, forcing prices up. The Lake pool, headed by Calumet & Hecla, In 1907, with further restriction of production, made a determined fight against this western the price reached 25 cents before the financial competition. Prices were slashed to discourage panic of that year. The price broke to about Montana producers, and by 1886 copper was half the 1907 peak, and as production from the selling at 10 cents a pound, compared to an new porphyries expanded, the price remained average price of more than 20 cents in the near the 13-cent level until 1912. previous decade. Western production, how- Increased supplies from Arizona, New Mexico ever, was scarcely checked, and the Lake pool Utah, and Nevada, made possible by large-scale was forced to admit defeat before the increasing exploitation of the great porphyry deposits, production of Butte wpper. In 1887, Butte would have broken the market if European production alone exceeded that of all Michigan. consumption had not been at an abnormally The price decline, following increased United high level. German demand in particular was States production, was accompanied by rapidly almost insatiable and not only held the mice increased consumption by the growing electrical around 13 cents but led to ah increase tb 18 industry. One of the most spectacular corners cents in 1912-13. in the history of market gamblers-the Secretan The domestic copper industry received tre- corner~ccurredat this time. By 1887, Secre- mendous impetus during World War I. Do- tan, a French financier, had contracted for mestic mines supplied 60 percent of the world three-fourths of the world copper and had begun primary copper during the war, and US.- to raise prices. Consumption fell while supplies wntrolled mines in other parts of the Western of newly mined copper and scrap flooded the Hemisphere supplied almost 20 percent more. market. As stocks increased, prim tumbled. The United States was the clearing house for Efforts to secure a reduction in the mounting world copper during this period, importing contract deliveries of copper failed, and in nearly all the production of other Western March 1889 the market collapsed. Hemphere sources and supplying most of the While the industry was recovering from the European demand. Secretan debacle and the price still hovered The immediate postwar period brought many around 11 cents, the ground was laid for a serious problems. To wpe with oversupply, new effort to corner the market-the Amalga- the industry organized the Copper Export mated pool, involving Standard Oil, National Association to operate in the export market City Bank (New York), and the Anaconda under the Webb-Pomerene Act. Huge war Copper MigCo. Their scheme was much stocks were liquidated in an orderly fashion, the same as that used by Secretan, and although and the industry was pulled through the acute the new combine did not attain its goal, for depression of 1921, while the average price was much the same reason that Secretan failed, maintained at slightly above theprewaraverage. the precarious position in which the industry Maintenance of the prewar price was far from found itself was saved in part by quiet liquids- satisfactory to an industry with inflated war tion of the Amal mated surplus copper stock wsts; but, considering that primary consump- holdings during ti e next 3 yem by a London tion in 1919-23 was 8 percent below the 190S13 banking firm. period and that productive capacity in the The industry had hard1 recovered from the Western Hemisphere had expanded 65 percent failure of Amalgamated Zopper Co. before it above the prewar kure, this was an accomplish- embarked on another price-raising attempt. ment of note. This organization did not The pool of 190647 was helped materially include foreign companies. by the rapid increase in consumption and the During the next 8 years, 1922-29, the swelling high level of speculative prosperity. Elimina- output of the mines of the Chide Copper Co., tion of the influence of F. Augustus Heinze in Braden Copper GI.,and (after 1924) Union 1906 strengthened the position of Amalgamated Miniere du Haut Katanga was more responsible at Butte. Under Federal mining law, the than any other single factor for keepi?g copper owner of the apex of a vein had the right to prices below the prewar level during thls period, mine the whole vein. In the complicated Butte bringing about the inactivation of the Copper vein structure, Anaconda and the Amalgamated Export Association in 1924. In 1926, Copper found themselves facing the possibility of losing Exporters, Inc., was formed under propisi?ns most of their ore in a legal battle with Heinze, of the Webb-Pomerene Act. This organization who owned a number of fractional claims on included producers of more than 80 percent of which his lawyers and engineers found the apex the United States mine production, representing HISTORY 33

all the outstanding units. With them were the tax was paid, and the metal that was ex- associated foreign producers, which, together ported in manufactured form was el' 'ble for a with the domestic members, controlled more drawback of 99 percent of the tax. 8d7 small than 90 percent of the world copper output. quantities of tax-paid copper were retamed in The new organization was a means of increas- the United States for ultimate consumption. ing the dominance of US. producers. By Business activity revived a little by 1933, eliminating the influence of speculators, who bringing with it relief for the copper producers. operated chiefly through the London Metal Thii trend of increased production continued Market, prices could be dictated by New York, for the next 5 years, except for a slight recession hce most of the world production and con- in 1938. sumption centered in the United SGates. The copper industry broke all roduction Whereas the Copper Exporters, Inc., did records in the 193949 decade. Refi nery out- succeed in fulfilling their first aim-reducing put soared from 1,126,000 tons in 1940 to the power of middlemen and eliminating the 1,502,000 tons in 1943, the pe& for the period. London influencethey were not as successful Although output decreased quantitatively after in their second stated aimstabilization of 1943, the amount of capacity being utilized price-for prices showed a strong tendency to averaged approximately 75 percent,which when rise. the excess capacity created by wartme require- This increase in prices was not at once ments is considered, indicated that the metal- apparent, for in 1927, the first full year of the preparation segment of the industry was in a Exporters activity, prices declined. At the relatively sound economc ,condition. How- same time, mine production decreased, a?d ever, domestic mines were incapable of sup- stocks increased. By 1928, however, the price plyin the production demands of the economy, of copper began to rise, bringing with it in- theref y forcing operators of smelters and creased production of primary and secondary refineries to rely more heady on unports of copper. This increase carried through 1929 unrefined copper. with the price for that year averaging 18.23 In Arizona in the 1950's the Lavender Pit, cents per pound, 24 percent more than in.1928, San Manuel, Silver Bell, Copper Cities, Puna, and mine production was at the second hghest and Esperanza m,ines started production; capac- point in the history of the industry. ity at the Ray rmne was substantially increased The copper industry had just begun to benefit by conversion from block caving to open-pit from rapid expansion of this era when the mining; and the Mission and Christmas mine stock-market crash came late in 1929. Produc- deposits were developed for production. The tion dropped sharply in 1930 and 1931, and by White Pine mine in Mich' an, the Yerington 1932 refinery output was 75 percent below the mine in Nevada, and the 2elley and Berkeley 1929 level. Copper Exporters, Inc., disbanded mines in Montana were brought into produc- in 1933. tion. United States mine production exceeded Of the 10 copper refineries operating at 94 all previous records in 1956 (1,104,156 short percent of their total capacity in 1929, 9 were tons) and almost reached this record in 1957 active in 1932 but were using only 25 percent and 1960; 1958 and 1959 were low production of their capacit because of the depression. years because of voluntary cutbacks in mine Anaconda, dnnecott, and Phelps Dodge in output and strikes. 1929 controlled 66 percent of the mine output Increasing demand in the United States and of the United States and 31 percent of the out- Europe beginning in the latter half of 1954 - put outside the United States, 48 percent of the created a copper shorts e, and the price qf major total world production. By 1932, however, the producers in the United" States rose contmually, combined share of these three companies had reaching 46 cents a pound on February 21,1956, declined from 48 to 36 percent of the world highest in 90 years. Prices quoted by custom total. United States production also declined smelters in the United States, the London from 47 percent to 23 percent of the world total. Metal Exchange, and other European markets Another event that had a far-reaching effect were even higher, attaining a peak of 55 cents on the United States copper industry was pas- per pound. (See chapter 6.) sage in 1932 of a 4-cent excise tax on all for- A number of substantial wpper properties in eign copper imports. This was e uivalent to a Canada began producing in the 1950's. Large 72-percent ad valorem duty base % on the aver- reserves were developed at the Toquepala, age price in 1932 and was practically an em- Cuajone, and Quellaveco deposits in Peru and bargo. Most imports of ores, concentrates, and at the El Salvador, Rio Blanw, Mantos Blmco, other unlinished forms of copper entered under La Africana, Chuquicamata, and Braden prop- bond for treatment and re-export without pay- erties in Chile. Additional sources of ore wefe ment of the tax. A small portion was imported, found in the wpper belts of Northern Rhodesia 34 COPPER and the Republic of the Congo. In Europe, mining technology effecting development of large deposits were developed in Yugoslavia, better mining methods, mining and transporta- at Majdanpek; the Glog6w area of Poland; tion equipment, explosipes, and engineering Ireland; E'inland; Bulgaria; and the U.S.S.R. control contributed to increasing output by Substantial ore bodies were found in Australia open-pit mining, accounting for 80 percent of and the Philippines. World mine production the copper ore and 75 percent of the copper increased progressively each year, except for produced in 1960. 1958, and in 1960 was 66 percent higher than 5. Rapid development of the flotation process in 1950. introduced in copper concentrators between 1913 and 1916. This process improved the TECHNOLOGICAL DEVELOPMENTS recovery of sulfide minerals from fine-grained ore fractions. Previously, the practice was to F'rimcipal technological developments in the use gravity methods to concentrate the ore, United States pertinent to the copper mining but ore that required line grinding to liberate and smelting industry during the past 100 minerals from gangue was not recoverable if years include the following: the average tenor was below the economic 1. Application of square-set mining, first limit of direct smelting. developed by Philip Deidesheimer in the early About 1921, the discovery that certain flota- 18601s, which solved the problem of mining the tion reagents could be used to effect separation large and fabulously rich, but soft and crum- of metallic sulfides from each other made avail- bling, silver sulfide ore body at the Cometock able additional tonnages of wpper and other silver mines of Nevada. The system was minerals in selective mixed ores. Selective immediately successful and has since found flotation can now make satisfactory separations worldwide application for ground support in of these minerals if the minerals themselves are mining ores that could not be mined by any not so intimately intergrown as to require other known method. excessive comminution to liberate them as 2. Introduction of a block-caving system at discrete particles. With introduction of flota- the iron mines in Michigan and the use of tion at the Utah Copper Co. mill after 1914, slushers for mucking, the forerunner of modern recovery was increased from 75 percent in that mechanical loading in underground metal mines, year to more than 90 percent by 1935, despite both near the close of the 19th century. These a general decline in the grade of ore treated. two developments were,not generally accorded At the Calumet & Hecla Consolidated Copper a prominent place in mming history, but their Co., Inc., mill, flotation was applied only to significance appears when viewed from the slime, and part of the indicated improvement perspective of later years. in recovery was due to leaching of sand tailiings. 3. Adaption of the Bessemer steel converter Up-to-date figures have not been compiled; to the conversion of copper matte into metal however, it is safe to assume that since 1935 in France in 1880 and in the United States in the percentage of recovery had decreased, owing the late 1880's. This development eliminated to the complexities and lower grade of ores the need for dead roasting copper sulfide ore being treated. By no means does this detract as a prelude to blast-furnace smelting to black from the effectiveness of this innovation, but copper. Previously, emphasis had been on the it does point up its limitations. treatment of oxide ores, and the worldwide 6. With flotation came a marked change in practice was to convert sulfides to oxides by copper-smelting methods. No longer was the cumbersome methods of roasting; in some cases blast-furnace converter cycle adequate, because this was followed by leaching, in others, by most of the fine flotation concentrates were blast-furnace smelting. The converter, with blown into the stack, and expensive recycling concomitant development of electrolytic refin- techniques were required to recover copper from ing to purify the resultant blister w per and to the dust. Again the steel industry made an recover its precious metals and other gyproducts, important contribution to wpper metallurgy- started electrolytic copper in the long, hard, the open-hearth steel furnace. Thls furnace competition to become accepted as equal, if not metamorphosed into the copper reverberatory superior, to Lake copper. The converter also furnace to smelt wpper concentrate into matte. was a major factor in lowering costs so that To control the sulfur content, partial roastmg lower-grade ores could be utilized. of fine concentrates to a Far~~liarcalcin~ befyi 4. The beginning of open-pit mining in 1907 reverberatorv srneltina rather than antennp permitted profitable exploitation of huge bodies for blast-furiace smeltkg gain,+ in importance of low-grade disseminated copper ores in the Later improvements in flotation now make ~t Southwest that previously had been considered possible, in many cases, to control the sulfur economically unworkable. Advancements in and iron in concentrates at the mill to eluninate roasting. And in 1960, Phelps Dodge Corp. 1896 Business recovered. initiated the use of reformed natural gas in 1898 Spanish-American War occurred. place of green poles for reduction in the anode 1899 Amal amated Copper Co., capital $75 furnaces of their smelters in Arizona. mdon, acquired +awnda. The following chronology indicates the major 1900- Was era of consolidations, mergers, and events important to development of the wpper 1905 financial wars for control of rich industry from 1850 to 1960, inclusive. Montana copper deposits. F. Augus- tus Heinze threatened Amalgamated- Anaconda mineral rights by securing CHRONOLOGY control of ke properties m Butte. Michigan mines became principal US. Amalgamated gought out Heinze for copper producers. $10.5 million, ending 5-year fight for First Atlantic cable was laid. control. Duty of 5 percent ad valorem, laid on "Rich man's panic" was experienced on er ingob in 1846, was removed. Wall Street, October. Ci%%'ar Ci%%'ar began. Daniel C. Jackling proved economical Duty was placed on copper ingots, etc., his idea of mining and processing the 2 cents a pound; on ores, 5 percent; low-grade copper-ores 6f the western and other copper, 25 to 35 percent ad United States on a scale previously valorem. unknown, thereby revolutionizing cop- Duty on copper ingots was placed at in the United States and 2.5 cents a pound until 1869. perabroad an makmg. available new and Civil War ended. "Greenback" infla- needed copper reserves to meet world tion occurred. requiremenis. Duty on raw copper was raised to 5 cents Braden Copper Co. in Chide began pro- a pound, 1869 to 1883; "Black Friday" duction of low-cost copper. occurred on Wall Street: first trans- World War I began. Clayton Act was continental railway was completed. passed. Calumet & Hecla consolidated the Micb- Kennecott Copper Corp. was formed. igan mines. Chide Copper Co. was m production. Panic of 1873 occurred. United States entered war; wpper was Rich copper deposits were discovered in laced under price control at 23.5 Arizona and Montana. cents a pound. - Edison invented incandescent lamp, World War I ended. Webb-Pomerene marking beginning of electrical in- Act was passed. dustry. Copper Export Association was formed. Anaconda Silver Mining Co. was or- Postwar inflation affected iodustq. ganized; copper mining bemn in Globe- Deflation occurred; "buyers' strike" en- Miami, &. forced; most copper mines were, shut First electric lamps were installed in down. Copper Export Association New York, December 20. ool removed 200,000 tons of copper United States became the leading world f'rom domestic market. copper producer. Katan a, Belgian Congo, began volume Duty on raw wpper was reduced to 4.5 p~ofuctlon. Co per Export Aasocia- cents per pound. tion was disbandd. Secretan acquired corner on wpper; 85 Copper Eqorters, Inc., was organized as percent of United States output was international copper cartel. controlled. Domestic copper production was cur- Montana became leading United Stah tailed, contrasting with upward trend producer. in demand. Secretan corner was broken by flood of Copper stocks were reduced to panic- new and scrap copper. buying levels. Baring Bros. failed because of copper Panic buying of copper continued; corner, preaipitatin~ depression of stock-market panic occu~ed,October; nineties. copper prices were pegged at 18.3 General Electric Co. was formed. New cents for nearly a year; Canada became York-Chicago copper telephone line large copper producer. was installed. Copper Exporters, Inc., was dissolved; Raw copper was placed on "free list." Rhodesian mines gained in volume Serious labor troubles occurred. production. COPPER

1932 Dutv of 4 cents ner nound was nlaced on wpper, steel, and aluminum. Ceiling raw copper ~&eil. pnce on copper was established Janu-

1933~ ~ ~ NRA (National Recoverv Act) Code for ary 26 by the Office of Price Stabis- Co per and Brass "Mill ' Products tion. World copper (free world coun- bfuq was aepond in November. tries) was placed under international 1934 NRA Co e for opper Industry price allocation and quotas were set by the was set at 9 cents er pound. International Materials Conference. NRA was declare8 unconstitutional. Chile embargoed copper exports to International Copper Control was United States, resultin in dual prices formed June 1. in United Statea. 2'elley mine at Copper production was curtailed by Butte, Mont., was started in pro- cartelSouth America, Africa. duction. Copper shortage brought panic buying Free trading resumed on London Metal and almost a 50- ercent price increase. Exchruige August 5 after lapse of 14 Business recession Lgan. years and on the New York Commod- World War I1 began September 1. ~tyExchan e after a recess of 2 yeara. International copper cartel was aban- Initial profuction came from Yering- doned. ton -e in Nevada. US. Government be an buying cop er Silver Bell, Lavender Pit, and Co per through RFC (8econstructlon %- Cities mines in Arizona and the Ate nance Corp.) subsidiary. Pine mine in Michigan reached pro- United States entered World War I1 duction stage. US.Government pur- December 8. Copper prices were chased 100,000 tons of Chilean copper. part under voluntary control San Manuel started production. Prices Co per prices were fixed at 12 cents, increased rapidly. 8onnecticut Valley, with a Govern- Mime production and price of copper ment subsidy for high+ost mines; reached record high in the United Premium Price plan set, February 1. States. Three-year labor contracts World War I1 ended. between principal producers and un- Price control was ended November 10. ions in United Stab were negotiated Rapid rice increases made Premium in June. Production was started at Price PL~ineffective. the Berkeley pit at Butte, Mont. Premium Price Plan was ended June 30. San Manuel Copper Corp. and White Geneva Trade Agreement was made. Pine Copper Co. delivered wpper to Excise tax was reduced from 4 cents the Government under DMPA con- to 2, pending ratification by Chile. tracts negotiated in 1952. Export (Tax was suspended during the war controls on copper were relaxed by and suspension was continued to Bureau of Foreign Commerce. March 31, 1949). Excise tax on copper imporb was re- Chile ratified Geneva agreement in imposed July 1 at 1.7 cents per ound February. Tax was further suspended pursuant to agreement at ~ATT until June 30, 1950. meetings at Geneva, in 1956. Korean conflict began June 26. Defense Principal copper mines, smelters, and re- Production Act was passed. Defense fineries were closed by longest stnke Minerals Administration in the De- in history. Operations began at the partment of the Interior, National Esperanza mine in Arizona in March. Production Authority in the Depart- Production was started in April at the ment of Commerce, and other agencies El Salvador mine in Chile. were created to carry out provisions of World mine production reached new the act. high. Scheduled production began at National Production Authority reinsti- the Toquepala mine in Peru, January tuted Controlled Materials Plan for 1. HISTORY BIBLIOGRAPHY

Aitcbison, Leslie. A Hlstor of Metals. V. 1 & 2, Latbmp, William G. The Braas Industry in the McDonald and Evans, ~d,London, 1960, 685 pp. United States. The Wihn H. Lee Co., New Haven, 1926. no. Benton, William. Co per Para. in Encyclopaedia Conn.. ,A. 21-22. Britannica, v. 4, GPhic~o,Ill., 1956, pp. 40 and Lemmer; Victory F. Prehistoric Copper Mines on the 9xL"dp.--~.--". Shorea of Lake Superior. Sk Min. Rev., v. 48, Bureau of Mines. Copper. MS 6, 1952. 694 pp. No. 40, Jan. 2, 1960, pp. 4-i215. Butte, Allison. Copper, The Metal, Its Alloya and Comnounds. Reinhold Pub. Coro.. New York. Marcosmn, Isaac F. Anaconda. Dodd, Mead & A, 1954; 936 pp. Company, Inc., 1957, 370 pp. Coghlan, H. H. Roman Mining in Britain. Optima, Mellor, J. W. A Comprehensive Treatise on In- Anglo-American Corp. of South Africa, Ltd., v. 8, organic and Theoretical Chemistry. Longmans no. I., March 1958, pp. 8-15. Green & Co., London, 1923, v. 3, p. 2; v. 6, p. 399. Copper Development hciation. Copper Through Roast, Harold J. Cast Bronze. Am. Soc. Metala, the Aam. Kendals Hd. Radlett. Hertfordshire. 1953, pp. 360-431. Engla

British Columbi.

Britannia The Amcondo Compmy M.nitoba Lynn Loke Shcrritt Gordon Mines, Lfd. Flin Flon Hudson Bay Mining & Smelting to., lnc. -&tori0 CHAPTER 3.-PRIMARY COPPER RESOURCES

The world is plentifully endowed with sources channels and replaced the sheared rock almost of copper. Mines operating today are equipped completely to form massive sulfide lenses. The and have the capacity to more than fullill cur- minerals are those of moderate temperature rent demand. New discoveries coupled with range of sulfide deposition, and the deposits extensions at mines in many copper provinces may or may not contain precious metals and of the world during the 1950's greatly increased zinc or lead in important amounts. Such the known world copper resource. Important deposits usually are not closely assoc~atedwith copper producing re 'ons of the world are: (1) igneous stocks, and none is m stocks. The western Unite f States, (2) the western The deposits of the deep1 eroded Appala- slope of the Andes in Peru and Chile, (3) the chian region belong to this cLsification, as do central African Copperbelt in Northern Rho- some of the deposits on the border of the desia and the Republic of the Congo, (4) the Sierra Nevada and Coast Range batholiths in Ural Mountains and the Kazakhstan region in California and British Columbia, res ectively, U.S.S.R., (5) the Precambrian area of central where erosion has also been deep. $he Ter- Canada, and (6) the Heweenaw peninsula of tiary deposits of the Rocky Mountain area, northern Michigan. Figure 2 shows location which have relatively shallow erosion, are not of major copper mines in the world. of this type. The primary ores are generally a rather low- GEOLOGY grade massive sulfide. Pyfihotite is in many of the ores, and ironrbearing spgresegreSent alente Deposits of copper are widely distributed, is in most of them. These mmerals are notably both eographically and geologically. Geo- absent in most of the Tertiary copper deposlt,s, logicaf y such ore bodies are found in a variety and depth of formation seems to be a factor m of host rocks of all ages under greatly varied their formation. structural conditions. The periods of their Supergene alteration in many deposits has formation range from Precambrian to Recent. produced a zone of enriched sulfides, usually Many are characteristically associated both in thin and rich as at Ducktown, Tenn., and Iron time and location with igneous activity, while Mountain, Calif., but sometimes deep and rich a few occur in sandstones and shales. as at Jerome, Ark Types of Deposits SUDBURY NICKELCOPPER DEPOSITS Theae are associated with the norite member Following is a general classification of types of the Sudbury irruptive. Generally, the ore of copper deposits; it should be recognized that bodies occur associated with faults at or near gradations will occur with gradual changes from the footwall contact between the norite and one physical and chemical environment to the underlyin volcanics or, m offsets of the another: (1) Lenticular deposits in schistose norite within t% e volcanic sernes. Structurally, rocks; (2) Sudbury nickel-copper type; (3) faulting appears to be the main ore-localizing native copper t es; (4) bedded deposits in feature, with ore bodies occurring in zones ,of sedimentary rocg; and (5) vein, pipe, and shearing and brecciation close to, the nonte disseminated deposits. contact. Ore occurs as dissemmated and LENTICULAR DEPOSITS IN SCHISTOSE heavy sulfide. types containing pyrrhotite, ROCKS pent andite, and chalcopyrite as the prmcipal minerals. Gold and silver occur as tellurides The primary mineralization of these deposits and in the native state. The platinum group consists of sulfides of iron, copper, and zinc metals appear as s errylite platmum arsenlde, commonly as a re lacement of schistose rocks. and other rare com\ination$. Schistosity may ge the result of widespread metamorphism, but the deposits are along NATIVE COPPER DEPOSITS zones of shearing. Such deposits seem to have Included are those in which the copper occurs formed at some depth under conditions that in shoots in tops of certain lava flows, in con- favored deformation by shearing rather than by glomerates interhedded with flows, and in brecciation or shattering. The solutions that sandstones. The rocks in which the copper deposited the ores were closely coahed to the occurs are characteristically red owing to the 39 40 COPPER presence of ferric oxide. The latter may showing such gradation that a definite separa- account for the copper being deposited as tion is neither possible nor desirable. The native metal rather than as sulfide. deposits are similar in mineral composition Deposits of this type have been mined at and differ mainly in the character of the frac- vertical depths of more than 6,000 feet in veins turing that has controlled deposition. and lodes with no notable change in min- Vein Deposits.-Perhaps, the simplest type eralogy. The ores are generally low-grade of deposit and the simplest veins are those concentrating ores, although large masses of that occupy a single fault or fissure. Large copper are present. copper deposits of this character are uncommon The Lake Su erior district of Michigan is the but are approached in the Magma vein of only large prockng region having depositg of Superior, Ariz., and the Old Dominion vein of this type, although similar deposits occur in Globe, Ariz. New Jersey, Pennsylvania, Maryland, Alaska, Other districts, such as the Butte district and Northern Canada. For many years native in Montana and the Morenci district in Arizona copper &o accounted for much of the produc- have complex vein systems in which the larger tion at the Corocoro mine in Bolivia. veins can be mined as units, but in parts of these areas a mass of small veins are mined BEDDED DEPOSITS IN SEDIMENTARY ROCKS together. These include contact or pyrometasomatic In general, the veins tend to join and decrease de osita and those formed by replacement of in number in depth, and a complex system of sec!mentary rocks, commonly limestone, out veins may merge into oqly a few root channels. ward from fissures. The two cleases arc not Volcanic Pipe Deposits.-These are more or sharply separated. The typical contact or less cylindrical bodies formed by volcanic pyrometasomatic deposits are replacements explosion. The rock within the pipe is usually of limestone or dolomite by silicates, oxides, brecciated, although in some a core of relatively and sulfides. Many contact deposits contain unbrecciated rock is surrounded by an envelope large bodies of andradite (the ferric iron of highly brecciated rock. The ore minarals garnet) with which are associated other high- cement and partly replace the brecciated rock. temperature silicates, iron o+des (magnetite In some pipes, quartz has replaced most of and hematite), and sulfides of won and copper. the rock in a central channel, while in others Many such deposits are in limestone at or replacement has been slight. near the contact of an intrusive body, usually Volcanic pipea range in size from a few feet a stock. or tens of feet to hundreds of feet in diameter The silicates and oxides formed first and the and in shapc from nearly circular to elongated, sulfides later. The sulfides, including copper resemblimg breccia veins. A few, hke the sulfide, are most abundant at many deposits Cactus pipe in Utah and the Colorado pipe between the silicate zone and the unreplaced at Cananea, Mexico, which have been followed limestone. In some deposits the silicate zone to what seems to be their roots, show a decrease is largely lacking, and the sulfide zone is close in area and less brecciation with depth. The to the igneous contact. Contact deposits pipe type of deposit has been particularly ade into fissure-replacement and bedded productive at Cananea and Nacozari, Mexico. %posits, in which certain beds of limestone Some of the disseminated deposits may be are replaced by sulfides outward from fissures large pipes such as the Utah copper deposits of with or without the formation of silicates. Bingham, Utah. In many of the pipes the Deposits of the contact metamorphic type ore minerals, disseminated as a breccia cement are widely distributed, especially in the eastern and replacement, comprise only a small part Cordilleran region, but with a few exceptions of the ore; in others, like the Colorado and have yielded relatively little copper. Part of Campbell pipes, parts of the ore bodies are the great deposits at Bisbee, Ariz., and some of massive sulfide. Most of the volcanic pipe the l~mestonereplacement deposits at Bingham, deposits are in the Tertiary of the eastern Utah, are examples of such occurrences, and Cordilleran region and were probably formed at shallow depth. many of less importance have been mined. Replacement Pipelike Deposits.-These occur With such deposits may be grouped those in in limestone and have been productive at many limestconefar from known intrusive bodies; the places; the Campbell ore body at Bisbee, h~., chalcocite deposits of the Copper River district is an example. These grade into the manto- in Alaska are outstanding examples. type deposit common in limestones and are VEINS, PIPES, AND DISSEMINATIONS generally formed by solution along intenectlng fractures. These may be grouped as three types of The origin of pipelike ore deposits is still open deposits, each having distinctive features but to question. In some the start was doubtless PRIMARY COPPER REBOURCEG 41 due to faulting or jointing, which formed brec- oxidizin process continues the ferrous sulfate rmeable channels were enlarged will oxiize to ferric sulfate, which may break cia%by solution These geefore the ore minerals were de- down to give limonite and sulfuric acid. posited. This has been referred to as mineral- Abundant pyrite gives abundant sulfuric acid. ization stoping. Pyrrhotite or more complex iron-copper sulfides In other pipes the character of brecciation may oxidize similarly but will yield less sulfuric has suggested that volcanic explosive action acid than pyrite. has broken a more or less cylindrical body of Formation of sulfuric acid and ferric sulfate rock. This permeable zone has later been promotes solubility of metals and is favorable traversed bv mineraliiin solutions which have to their movement in ground water. The cemented and partly repf aced the breccia. presence of iron sulfide, especially pyrite, The importance of pipelike deposits depends therefore favors leaching of copper. on the distinction that is drawn between them and other types, but typical pipelike deposits CHARACTER OF GANGUE of both types have produced much ore. Disseminated (Porphyry) Deposits.-In Gangue minerals have been classed as North America this is confined to the eastern reactive, intermediate, and inert. Cordilleran region. It occurs characteristically The carbonates, calcite and dolomite, are in and around the to s of intrusive bodies that most reactive; the micas, feldspars, and other probably are upwar j extensions of batholitic silicates are intermediate; and quartz and intrusions. The intrusive bodies may therefore barite are inert. An inert gangue, such as be simple upward projections in the form of quartz, has no chemical influence on the stocks or cupolas, or they may follow structural oxidation products of sulfides and is favorable features and be modified forms of stocks or to their movement. Reactive gangues, such cupolas. Some of the disseminated deposits, as calcite and dolomite, react with all the such as those of the Bingham district, Utah, oxidation products of sulfides, neutralizing and the Ely district, Nev., are in such modified sulfuric acid, precipitating the metal sulfates stocks. as carbonates, and causing recipitation of Along the boundary of the stocks both the limonite from ferric sulfate. !he presence of intruded and the intrusive rocks have been calcite or dolomite is unfavorable to the move- jointed and fractured. The fracture zones were ment of co per and tends to produce copper subsequently mineralized, mainly with pyrite carbonate &posits in the upper parts of the and chalcopyrite in variable amounts and pro- oxidizin body rather than a zone from which portions. In some deposits, such as those of copper f as been leached. With an abundant Bin ham, Utah, most of the mineralization is carbonate gangue there will be little downward in t% e stock; but some extended into the in- movement of wpper. With a quartz or truded quartzite, while in others, such as those silicate gangue there may be much downward of Miami, Ariz., much of the mineralization is movement. in the intruded schist. The primary mineral- As the copper sulfate, other sulfates, and ization is characteristically low in grade but sulfuric acid move below the zone of oxidation with wide variations. The deposits have all they encounter fresh sulfides, and the copper undergone oxidation, which has affected them is precipitated on these as copper sulfide. differently. Precipitation may result from direct reaction between the wpper sulfate and the sulfide or Effed of Oxidation on Copper Deposits hydro en sulfide may precipitate sulfides from the s& ate solutions. The effect of oxidation on the value of copper deposits is perhaps greater and more varied than TYPE OF DEPOSIT for any other metal. Several factors influence oxidation: In massive sulfide bodies, such as the lenses in schist, the copper is precipitated before the 1. Character of the sulfide, particular1 the solutions have penetrated far into the sulfides, proportion of yrite to copper sulfiB e or resulting in a shallow zone of supeqene copper-iron sulfiles. (secondary) sulfides which in some deposits is 2. Character of the gangue minerals or very rich. This precipitation is due to the enclosing rock, whether reactive or nonreactive. abundance of fresh sulfides. 3. Type of the deposit, whether massive In disseminated deposits the sulfate solutions sulfide or disseminated sulfide. penetrate deep into the zone of scattered sulfide CHARACTER OF SULFIDFS grains (mainly pyrite and chalco yrite) before all the copper is precipitated, anf. a thick zone Pyrite (FeS2) in oxidizing is first chan d to of secondary sulfide is produced which is usually ferrnus sulfate and Bulfuric acid. IF the not rich. The zones migrate downward during weath- TABLE6.-Principal copper minerals ering, and oxidation of the secondary sulfide zone may produce a relatively rich zone of carbonates and oxides. The water table prac- tically limits the downward movement of oxidation. Native: Native mpper .... Cu ...... 8.8 -8.9 0 oxides: lm. The net result of oxidation is the formation of Cuprite...... Cur0...... 6.0 88.8 four zones, any one of which, exceot the lowest TBnOnte ...... CUO ...... 5.8 -6.3 70.8 Malachite ...... ouC01Cu(oH)~.... 3.9 4. a1 57.3 or zone, may be lacking: ' ~~urite...... ac~corc~(ox),... 3.77 55. I Chrysomlla...... CuSiOBHrO ...... 2.0 -2.4 38.0 1. An upper zone from which copper has been Antlerit8 ...... CurSOdOBh ...... 3.39 54.0 leached. Bmchaotits...... CugOdOHh ...... 3.39 €4.2 Atacamlte ...... CuClr.nCu(0E)1.. 3.75-3.77 59.4 2. A zona in which copper has been fixed as Sulfides a carbonate. Chalmpyrite...... CuFeL...... 4.2 4.3 31.5 Bomite...... -. CurFeSa...... 4.9 -5.4 63.3 3. A zone iu which copper leached from Chslmdte...... CurS ...... 5.5 -5.8 79.8 Covellite ...... CuS ...... 4.9 -LO e8.4 above has been deposited as secondary sulfide. Enmte...... GtuAslS~...-...... 4.434.45 48.3 Tstrahedrite ...... CuC3b& ...... 4.7 -5.0 521 4. The zone of primary sulfides. Ten-tite ...... CuaAsoSi...... 4.7 -5.0 57.0 Mineralogy extent, bornite may exist in outcrops or /n COPPER MINERALS float, but when found at the surface in and Copper is found in nature in numerous districts usually they are as kernels surrounded minerals and in various combinations with by alteration products. Copper sulfides are other elements. Of 165 known copper minerals generally associated with pyrite and other iron only about 12 are commercially important; sulfide minerals. about 6 minerals are the source of more than 95 percent of the copper mined. Principel COPPER ORES copper minerals are listed in table 6. Copper ores vary in type (whether sulfide or There are three important groups of copper- oxide), in the valuable metals occurring in them, bearing minerals. The first is that of the in tenor, and in the kind of associated gangue primary or hypogene minerals, those deposited present. They are commonly distinguished as at considerable depth in the earth by processes oxidized ores or sulfide ores and may range that may be related to igneous activity. between high grade and low grade, the grade Examples of these are bornite, chalcopyrite, roughly expressing copper content. and enargite. Some complex minerals are A sulfide ore is a natural mixture contaFng also primary, but minerals of this type are not copper-bearing sulfide minerals and associated abundant in economic deposits. gangue minerals that are either valueless, ss The second group is composed of the super- regards their metal content, or of subordinate gene copper minerals commonly formed by importance for some other purpose. The weathering of copper sulfides. Cuprite, mala- gangue may consist simply of the minerals chite, azurite, and chrysocolla are the chief making up the host rock, or it may be composed minerals of the supergene zones of copper of various other minerals developed durmg the deposits when a reactive gangue is present. general ore-forming process, or it may occur as Brochantite and atacamite are found in the a combination of these two groups. Thus the upper portions of ore bodies in arid regions. gangue might consist of a sulfide, such as py- The third group, the simple sulfides, chalco- rite, along with quartz, sericite, calcite, barite, cite, and covellite, are predominant in the zone etc. From an ore like this, in addition to the of seconadry enrichment. These minerals may principal value in copper, pyrite might be also be found as primary minerals in some reclaimed as a byproduct for its sulfur, and deposits. barite might be recovered to be used in well- The copper minerals found most frequently drilling muds. at the surface are the green and blue copper An oxidized copper ore is similarly a natural carbonates ,and the green silicates. These mixtureof oxidized copper m+erals and gangue. colors are distinctive; however, a rock with a Examples would be malach~teand azurite ,m very small percentage of copper may be colored dolomite stained by iron oxide, or brochantite green. Cuprite, tenorite, native copper, atac- and crysocolla deposited among silicates. amite, chalcanthite, and occasionally other rare Although there are many ores in which copper copper minerals are found in outcrops; these is dominant and is the principal metal recovered, minerals, together with the carbonates and for some copper-bearing ores much of the value silicate minerals, are formed by weathering of comes from other metals associated with copper copper sulfides. Chalcopyrite and, to a smaller or from nonmetallic constituents. Other prod- PRIMARY COPPER RESOURCES 43 ucts commonly contribute to the value of a carrying some of the copper as enar ite or copper ore. tennantite, containing arsenic. Well-$, own Commonly associated with copper are minor deposits of this kind are at Butte, Mont.; amounts of gold and silver and locally lead Bor, Yugoslavia; the Cordilleran region of and zinc. Molybdenum is recovered in several South America; and Tsumeb, South-West plants treating porphyry copper ores, and very Africa. minor amounts of platinum, selenium, etc., Various groupings of oxidized copper ores may be extracted in refining. Nickel, likewise, may be made according to their response to occurs in certain kinds of wpper ore, and cobalt metallurgical treatment. For example, we may is a valuable associate of copper in some ores recognize (1) the malachite-bearing ores in of the Belgian Congo and Northern Rhodesia. dolomite of the Congo that are successfully Mineralogically, a sulfide ore might contain, concentrated by flotahou; (2) the various mix- for example, chalcocite and pyrite dispersed tures of malachite, azurite, chrysocolla, and through a gangue of sericite schkt; chalcocite, tenorite that are subject to treatment by leacb- chalcopyrite, and pyrite with a little molyb- iug with sulfuric acid; and (3) the unusual denite might be associated with gangue minerals oxidized mineral assemblage at Chuquicamata, derived from the alteration of quartz mon- Chile, consisting principally of brochantite, zonite rock. atacamite, antlerite, chalcanthite, krohnkite, In some ores, copper occurs in coordinate im- and natrochalcite, also treated by leaching. portance with other valuable metals to form In addition, there are various mixtures of a so-called complex ore. By skillful benefi- oxidized and sulfide copper minerals occurring ciation, for example, lead, zinc, and copper together in ores that are treated by leaching might be recovered from such material. Sulfide or by leaching followed by flotation. minerals in this kid of ore might be galena, There are ores in which copper is carried as sphalerite, chalcopyrite, and pyrite contained the native metal. In these the gangue may be in a gangue of limestone or dolomite. Or, the conglomerate or basalt, as in the ores from the ore might carry nickel and copper with a sulfide Lake Superior district in Michigan, or sand- assemblage of pentlandite, chalcopyrite, and stone, as in the much smaller deposits at pyrrhotite in norite. Corocoro, Bolivia. Copper itself may occur as a byproduct in The kind of gangue accompanying a copper some ores, and its value may be only a subordi- ore may be of considerable importance in its nate item as in some of the large zinc-lead, miuiue and treatment. The mineralom. tex- nickel, and iron deposits. ture, &d physical characteristics of thegangne, Copper ores vary widely, and the usual which is eenerdh the ~re~onderantmaterial. practice is to group them into high-grade and may dictcte the iype of &ing method to be low-grade categories. In the United States employed. Similar factors control crushing, most copper comes from the miniue and concen- grinding, classification, and flotation of the ore trating of ores carrying from 0.4 to 1.20 percent during its treatment. copper,-- . mainly in the sulfide form: the general Copper ores are found with diverse textures, average content of recoverable copper is about depending upon the size, relative abundance, 0.80 percent. High-grade ores commonly con- and arrangement of their constituents. Ores tain from 3 to 10 percent copper, although some in which the sulfide grains are scattered through may be richer, and are generally smelted direct the host rock are proper1 termed disseminated without preliminary concentration. ores. However, when t Ke sulfide minerals are Among the sulfide copper ores, three out- aggregated together in rich abundance, the ore standing groups should be noted. The first ated as massive sulfide. Or, if the is composed of the porphyry copper and valuabis desi$ e mmerals. occur in a multitude of vein- Northern Rhodesian types that carry copper lets, it is called a stringer ore, or a stockwork. mostly in the form of chalcocite, chalcopyrite, In summary, the type of copper ore (whether and bornite-iron being contained in pyrite, oxidized or sulfide), its richness in cop er, the chalcopyrite, and bornite. Copper ranges in amount of accompanying metals of vaf ue, the amount from a fraction of one percent to several content of substances detrimental to treatment, percent, and iron is generally low to moderate the kind of gclngue, and the texture and hard- in amount. A second group includes the de- ness of the ore all influence the selection of posits commonly known as cupriferous pyrite methods for its treatment. bodies. These contain very abundant pyrite and pyrrhotite and are high in iron and sulfur. WORLD RESERVES Copper is carried in these ores by chalcopyrite generally ranging from 1 to 3 percent. Notable The total reserve of copper in the world is examples are at Jerome, Ariz.; Rio Tinto, Spain; presently estimated to be 212 million tons or and Cyprus. A third group comprises the ores enough to last about 50 years at the current 44 COPPER TABLE7.-World copper reserves the ore completely or to establish its grade throughout. Ore tp Ore re- Inferred ore.-Quantitative estimates are serve8 serves WPW WPW Cmtm -tent, Camtm mtent. thmr thou. sand sand measurements., The short short toas tons assumed contmuity -- or repetition for which there is specific geologic Nmth Adca: Ada: evidence of their presence. Estimates of in- Caoads...... Chlns...... cubs ...... 8,100m 3,mm ferred ore should include a statement of the EslU...... 76 PnZ.1::::::::::::: Irn special limits within which the inferred ore may Merim...... 750 Isas1 ...... asl Uniwd stam ...... 32,100 Jaw...... 1.m lie. - Phlupplnes...... l,mO TOW ...... 41,923 Turkey ...... 3% Physical measurement of ore deposits is only %"th Amcrlea: - one of the factors in determming the size and RoU?ia ...... 65 cm ...... ym '....-. grade of reserves. In addition, ore reserves Peru...... 12,m Angola...... 40 - hpubuo of tbe increase as technological advances lower costs TOM...... %, 6.55 coogo ...... m,m and permit the mining and processing of lower Emp: Northern Rhodesia.. 25,m Ausma ...... a &uth RbodesiB.. 416 grades of ore. And, because the grade of ore S"I&S ...... m Kenya ...... al Finlsnd ...... 1M Msurltsnia ...... 4ol mined is &o dependent on the market price of Emaermaoy ...... 100 BoutbWest Ames... 516 copper, a rise in price will automatically make Irelsnd...... 280 Uwda...... 210 Nm...... 100 Repubuo of sonth avadable supplies of ore previously uneco- Poland ...... 11,400 Ahiea ...... 800 nomidal to mine. A lowering of the price or spsln ...... 4,100 Saeden...... m0 any condition or event increasing the cost of U.8.S.R ...... a6,m Yugdavla ...... -a, ?so production, such as inflation, will have the To...... reverse effect of raising the economic grade of 54 140 ore that can be mined and reduce the reserve of copper. The grade of ore that can be mined annual production rate of slightly more than and processed economically differs from country 4 million tons. The tabulation of reserves by to country, from district to district, and from country and continent in table 7 is from mine to mine, depending upon the factors estimates reported in a variety of sources for that influence cost. Location, water supply, ificant copper producing areas of the world. transportation, and metallurgy are some of the 3" quantities shown were considered to be conditions that sect costs and may determine measured or indicated ores that were minable whether or not a deposit can qualify as a under technologic and cost-price conditions reserve. prevailing in 1960. There is little doubt that potential copper Standard definitions for the three categories resources are 'very large and, as demand of reserves a eed to b the Federal Bureau of increases and old deposits become depleted, Mmes and Federal 6eological Survey were new deposits must be found and developed. used in appraising the estimates. The defini- An outstanding feature of reserve forecasts over tions are: the past three decades has been the upward Measured Ore,-Tonnage is computed from trend in the quantity available, despite the dimensions revealed in outcrops, trenches, large tonnage of ore mined. Table 8 shows this workings, and drill holes, and the grade ia wm- rogression of copper-reserve estimates for the puted from results of detailed sampling. Sites bnited States since 1931. for inspection, sampling, and measurement are In summary, the copper reserve picture for so closely spaced, and the geologic character is the world assures a plentiful supply of copper so well defined, that the size, shape, and mineral for many years to come. content are well established. The corn uted tonnage and grade are accurate within imits PRINCIPAL COPPER MINES IN THE which are stated, and no such limit differs from the computed tonnage or grade by more than WORLD 20 percent. Indicated ore.-Tonnage and grade are North America computed partly from s ecific measurements, UNITED STATES samples, or production Xata and partly from projection for a reasonable distance on geologic The principal sources of copper in this evidence. The sites available for inspection, country are in the Weste.m States. In 1960 measurement, and sampling are too mdely or copper production was reported from 16 states otherwise inappropriately spaced to outline and reached 1,083,000 tons after falling below (PRIMARY COPPER RESOURCFA3 45

TABLE8.-T~end of U.S. cop %--reserve estimates - - Annual rate Year Tom recoverable Price, Life, of productio Reference copper cents years used to esti. - mate life, ton 1931 At least 18. 500.000.- 600,000 Barbour. Perw. World doooer-ore- - Reserves. Eng. and Min. J., vl. 131, p: 178. 1931 18,800,000...... 600,000 Rawles, W. P. The Nationahty of Commercial Control of World Minerals. AIME, Contr. 41. '"*"Lno.,. 1934 600,000 ur, Perev. World Co~rnr-Ore Reserves. 1935 750,000

1936 725,000 Do. - 1944 800,000 Cannon, R. J., M. Mosier, and Helena Meyer. Mineral Position of the United States. Dept. of Interior, 1947, pp. 24&241. 1945 800,000 Federel Trade Cornrmssion Report on the Copper Industry, 1947, p. 4. 1960 1,100,000 US. Geological Survey and US. Bureau of Mines. - the million mark in 1958 and 1959; the mines that year to 12,000 tons in 1960. In 1954 in six states furnished 97 percent of the. 1960 the Bagdad ore rgserve was estimated at 30 output. These were: Arizona, Utah, Montana, million tons of sulfide ore, averaging 0.754 Nevada, New Mexico, and Michigan. percent copper, and 30 million tons of leacha- ble oxide-carbonate material, containing 0.435 Arizona ercent copper. A dump leaching plant was Bagdad Mine.-In western Yavapai County, !.udt m. 1960 to recover copper from a sub- this is 27 miles by road from Hillside, a station stantial mine dump containing soluble copper on the Santa Fe Railway. The ore body at minerals. Bagdad is a chalcocite-enriched zone in gray Christmas Mine.-In Gda County, 8 miles quartz monwnite porphyry that crops out in north of Winkelman and 22 miles south of the form of an irregular stock, roughly 2 miles Globe, this mine was opened in 1905 and was long (east and west) and 1 mile wide (north and worked intermittently for fifty years producing south). It joins a complex of older rocks on approximately 1,500,000 tons of ore averaging the north and is enclosed by a granitic complex 2.4 percent copper. on the other sides. Some roof pendants of the The Inspiration Consolidated Copper Co. older granite are present in the stock of quartz began intensive exploration and development monzonite. The northwest-trending Hawkeye in 1954 of underground drifting and both surface fault cuts through the quartz monzonite and and underground drilling, developing an esti- the ore body and dips 70' to 80' in an easterly mated proven and probable ore reserve of 20 direction. The chalcocite ore body is present million tons containing 1.83 percent copper. on the dropped hanging-wall block but is absent The chance of developing additional ore is on the footwall side. Numerous minor frac- reported to be good. tures cut the quartz monzonite in the vicinit The mineral deposits are of the contact meta- of the ore body. The principal sulfide minera Ps morphic or pyrometasomatic type. The ore are pyrite, te, and molybdenite. body is tabular and ranges from 20 to 100 feet The minerals chalcOF gener y are scattered as grains in thickness. Chalcopyrite is the most abun- through the monzonite but in places occur in dant ore mineral, but variable amountsof bornite, veinlets of quartz. Some galena, sphakrite, chalcocite, and oxidized coppcr minerals are and bornite are found in the monzonite. In the upper or oxidized portion the quartz generally present. The gangue is chiefly monzonite shows alteration by sulfuric acid garnet, quartz, magnetite, and unreplaced solutions generated b oxidation of the sulfides. limestone. The factors that controlled the A change from b9 ock caving to open-pit localization of the ore minerals are: (1) mining was made in 1948 and the annual pro- Proximity to the limestonequartz diorite con- duction of copper advanced from 7,000 tons tact, (2)favorable character of certain limestone 46 COPPER beds, (3) gametieation of the limestone, and but most of it was confined to fractmes. Sub- (4) postgarnetization fracturing. sequent oxidation produced the silicates, car- Development completed by the end of July bonates, and oxidei-providing a major source 1962 included sinking a hoisting shaft 18 of the copper mined. feet in diametar 1,793 feet, a ventilation shaft The conversion from undermound block cav- 12 feet in diameter 1,033 feet, and driving the ing to surface open-pit mhg, which was 1,600 level haulage drift between the hoisting started in April 1948 and was completed in shaft and the ore body. The 4,000-ton-per- August 1954, together with successful develop- day concentrating plant began operating in ment of the Dual Process for treating mixed in August 1962. Concentrates are trucked oxidesulfide ore by leaching followed by flota- 37 miles to the Inspiration smelter in the tion, resolved certain operational problems, Globe-Miami district. lowered costs, allowed profitable treatment of Esperanza Open-Pit Mine.-The Duval Sul- lower grade ores, and increased ore reserves. hur & Potash Co. mine, 28 miles south of The high-average ratio of waste removal to ore 5ucson, started production in March 1959 after mined dropped from more than 3 tons of waste completing an extensive surface drilling and per ton of ore to 1.83 tons in 1957 and to 1.18 underground exploration program, initiated in tons in 1958. Construction of facilities for re- 1955, and removing about 6 million tons of cover of b product molybdenum was com- waste. Pmduct,ion capacity is expected to pleted: and pyant operation commenced in April reach 12,000 tons of ore per day from a reserve 1958. The company mining engineers esti- of 49 diontons, averaging 0.75 percent copper mated the proven ore reserve in the Inspiration and 0.022 percent molybdenum. mine to be 444,000 tons of recoverable copper The ore body is an enriched blanket averaging as of December 31, 1958. 130 feet in thicknesk and is covered by an aver- Lavender Pit and Copper Queen BIines.- age of 95 feet of overburden. The ore is local- These Phelps Dodge Corp. mines are in the ized in three types of rocks: (1) A series com- Warren miniig district at Bisbee near the posed largely of graywacke, arkose, and southeast corner of Arizona. Since 1880 this conglomerate breccia; (2) an intrusive andesite; area has been one of the major sources of copper and (3) a quartz monzonite porphyry. There is in the United States, having furnished over an unusually regular chalcocite enriched blanket 234 million tons from within an area of 4 square with a capping of about the same thickness, but miles. the protore is rich enough in places to constitute At Bisbee Pre-Cretaceous rocks were in- ore, especially where it has a good molybdenum truded by the Sacramento Hill granite porphyry content. The primary mineralization is com- stock, and after considerable erosion the Divl- posed of quartz, clay minerals, biotite, chalco- dend Fault with a displacement of 2,000 to pyrite, molybdenite, and minor pyrite. 5,000 feet truncated the porphyry chimney. Inspiration Mine.-The Inspiration Consoli- Mineralizing solutions came after the intrusion dated Copper Co. mine, formerly an under- in various fracture zones in the limestone and ground block-caving operation, consists of two followed porphyry dikes and sills. Oxidation open-pit properties, the Live Oak and the and secondary enrichment in the mineralized Thornton, in the Miami-Inspiration ore zone, granite porphyry produced a siliceous iron about 6 miles west of Globe. This ore zone is bearing gossan underlain by secondarily en- in Precambrian Pinal schist, which is chiefly a riched low-grade ore bodies. Prior to 1917 sericite schist consisting of quartz, sericite, and the porphyry stock was drilled and two ore biotite. The principal intrusive masses closely zones were proved, known as the East and associated with the ore deposits are the Schultze West ore bodies. The West ore body was granite and the Lost Gulch monzonite. elliptic in shape with a major axis of 1,200 feet The ore occurs in blanket deposits as dis- and a minor axis of 800 feet; it contained chal- seminated chalcocite or oxidized copper miner- cocite, some bornite, chalcopyrite, and con- als or mixtures of these in both schist and siderable pyrite in a siliceous gangue. This porphyry close to the porphyry contact. The ore body was mined from 1917 to 1929 as the porphyry and schist were thoroughly shattered. Sacramento open-pit mine, producing 159,000 Then mineral solutions permeated the or* zone tons of copper. through minute, closely spaced fractures and Stripping of the East ore body (Lavender deposited the sulfides together with silica in a pit) was started in 1951, and by 1959, 202,000 very irregular network of veinlets. The pre- tons of copper had been produced. dominant sulfide deposited was pyrite, with In 1954 the ore reserves of the Lavender pit very subordinate chalcopyrite and molybdenite. were estimated to he 41 million tons of 1.14 The feldspars of the porphl-ry were attacked percent cop er ore and 31 million tons of and partly sericitized by the solutions. A little low-grade s15 fide suitable for leaching wlth an sulfide penetrated the walls between fractures, average grade of 0.42 percent. These reserves PRIMARY COPPER RESOURCES 47 were estimated to last 12 years at a production percent copper. Of this, 729,000 tons of 7.22 rate of 16,000 tons of ore per day or 38,000 percent ore were in the bedded ore body. tons of copper per year. Planned expansion of Miami IUine.-Now owned by Tennessee Corp. the pit announced in 1959 indicated the develop this mine began operating in 1911, and to the ment of sufficient ore to last 15 years at the end of 1959 it had produced 1.186 million current rate. tons of copper. During the last few years of Ore bodies south of the Dividend Fault are operation, underground mining at this property deep and are mined by underground methods. was carried on, in part, to break up the remain- They are of two distinct types: A pyrite ing low-grade area preparato to producing periphery roph ry contact type and an wpper through in-place leac7. mg. In 1960 megular-be$ repLcement type. Ores of the approximately ,10,000 tons of copper was pro- former have a more massive character, while duced by th~smethod. Intensive studies those of the latter tend to be tabular, since the indicated economic advantages in the conver- shape of the ore body is usually influenced by sion to a total leaching operation which was bedding of the limestone replacement. To accomplished in June 1959. The Castle Dome remove the ore the open-stope, cut and fill, and open- it copper mine, belonging to the corpora- square-set stoping methods are used. tion, {egan operating in 1943; operations were Mining began in the Copper Queen under- terminated in 1953 after approximately 249,000 ground unit in 1880. By the end of 1959 tons of copper had been produced. After the about 3 million tons of copper, 90 million ounces mining was terminated the dumps were prepared of silver, 2 million ounces of gold, 143 thousand for leaching, and the company continued to tons of lead and 168 thousand tons of zinc produce about 2,500 tons of copper per year by was produced. During the last several years this method. During 1961 and 1962 plans were copper has been produced at the rate of about prepared and a plant was constructed to leach 30,000 tons per year. Reserve data on the the mine dumps of the Copper Cities mine by Copper Queen mine are not known. the same method. Production from the dumps Mngma Mine.-This Magma Copper Co. of this mine will replace the production from mine is at Superior about 65 miles east of the Castle Dome mine as it is depleted. Phoenix in the Pioneer (Superior) mining Copper Cities Open-Pit Mine.-Also owned district, Pinal County. The mine has been by the Tennessee Corp. this is 3 miles north of successfully operated almost continually since the Miami mine. The deposit is a typical low- 1910. Production in recent years has been in grade dissemination of chalcopyrite and chal- the range of about 450,000 tons of 5 to 6 percent cocite in uartz monzonite and quartz-mon- copper ore, annually yielding from 20,000 to zonite porayy. A churn-drilling exploration 27,000 tons of copper. Two types of ore bodies program, started early in 1946 and completed are found in the Magma mine. Most of the in 1949, developed an ore reserve estimated at ore has come from steep dipping vein deposits 33 million tons carrying 0.7 percent copper. which are developed for a maximum distance of An additional 9 million tons was discovered by 9,000 feet along the strike of the vein and to a drilling in 1956. The ore reserve as of January depth of 4,900 feet below zero level, or to an 1, 1959, was estimated to be 29.2 million tons. elevation of 1,370 feet below sea level. The Stripping began in June 1951 and initial principal ore mineral in the vein ore bodies is mining of ore began in August 1954. Sulfide chalcopyrite with enargite, bornite, and hypo- ore is mined and is concentrated at 12,000 tons gene chalcocite found in varying abundance. per day for an annual production of approxi- Replacement ore bodies were discovered in beds mately 18,000 tons of copper. cut by the vein systems in the eastern end of Mineral Hill Mine.-This is 16 miles south of the mine about 1949. Here the mineralization Tucson and 8 miles west of Sahuarita, in the extends away from the veins along favorable Pima Mining District. The Banner Mining beds for more than 500 feet and in some places Co. optioned the property in 1950, ohtained a as much as 800 feet. The average thickness Defense Minerals Exploration loan, and began is around 15 to 20 feet but at times reaches an exploration program. A substantial ore 30 feet. In the replacement ore bodies impor- body was discovered, and the company began tant copper minerals are chalcopyrite, bornite, a development and construction program that and chalwcite. At the present time more than brought the mine into production in 1954. half of the ore wmes from the replacement ore Two ore bodiesabout 3,000feet apart;the Mineral bodies. About 400,000 tons of ore or about Hill and the Daisy, were developed. The Daisy 20,000 tons of copper is produced per year. ore body was developed fint by diamond-drill The ore also contains a significant amount of holes from the surface then by a 450-foot silver and gold. vertical shaft. Some of the ore was within 25 On January 1, 1962, the ore reserves were feet of the surface and was localized along a estimated to be 882,000 tons, averaging 7.06 northeast to east striking fault, which probably is a segment of the Mineral Hill Fault. Ore The company constructed a 15,000-ton-per- occurs in sedimentary rocks in a zone near the day concentrator, and production of 45,000 contact between Permian limestone and quartz- tons of copper annually was begun in July 1961. ite; the best ore is in the limestone. The ore reserve has been estimated at 65 million Copper deposits at Mineral Hill mine are of tons of 0.9 percent copper. the contact metamorphic type. The east-west Morenci Mine.-This PheI s Dodge Corp. pre-ore fault traverses the property for about property near the town of CliP. ton in southeast- 5,500 feet with some minor offsets in one of ern Arizona is the largest producer of co per in about 400 feet. Ore mineralization is localized the State and ranks second in the bnited along this fault zone at and along intersections States. Ore is mined at 52,000 tons per day with cross faults and at or near intrusive by the open-pit method; it is concentrated and contacts in limestone and quartzite. The main smelted nearby. Blister copper is cast into deposit is formed in the sedimentary rocks near 700-pound anodes and shipped to the Phelps the fault contact with a granite stock at or near Dodge refinery in El Paso, Tex. Molyhdenite the intersection of two faults. The copper is recovered as a byproduct. ores occur as replacement in the limestone along Three t es of ore bodies occur in the Morenci shear zones and as disseminations in contact district. They are: (1) Irregular or roughly circuits. The main copper mineral is chalco- tabular contact-metamorphic bodies in lime- pyrite with small amounts of chalcocite and stone or shale near porphyry; (2) lodes or veins bornite. Exploration was continued in an area in fault zones; (3) irregular deposits of low- north of the Mineral Hill deposit and a major grade disseminated ore in porphyry. Early ore body was discovered. A 5-compartment production of approximately 991,000 tons of shaft was sunk 1,700 feet deep on the new copper came from ore bodiea of the first two deposit, and full production began at the end of types. 1961 from ore too deep for open-pit mining. The open-pit ore body, a disseminated deposit Exploration of the Palo Verde ore deposit has of the third t e, is in a medium hard monzonite developed 58 million tons of ore of a grade porphyry. 8eaverage thickness of the cap- comparable to that produced by open-pit ping was 216 feet, and the maximum thickness mining. Reserves at the Mineral Hill and was about 500 feet. The ore extends through a Daisy mines are unavailable. About 1,000 tons vertical range of about 1,300 feet, and the of copper ore is produced per day. surface outline of the ore body forms a rough Mission Mine.-The Mission project of the oval-covering approximately 900 acres. Some American Smelting and Refining Co.-formerly oxidized+opper minerals are present in part of called the East Pima-is about 15 miles south- the capping. This is considered leach material west of Tucson where the company started and is dumped where provision can be made for exploring the deposit in 1954. During the extracting the copper content at some future following 5-year period 346 holes totaling date. The principal sulfide minerals are chal- 190,000 feet were diamond drilled and 2,200 code and pyrite. Chalcopyrite and bornite feet of underground workings were driven to have been identified and covellite is present test the potentiality of the ore body. in minor amounts. The chalcocite occurs as a The deposit lies within an extensive zone of coating on pyrite and alw is present as a dis- porphyry-copper type alteration-mineraliza- semination in the gangue. tion in sedimentary rocks that have been Mining began in 1942 on the o en pit ore folded, faulted, and intruded by monzonite body, estimated to contain 284 milion tons- porphyry. Disseminated pyrite and chalco- averaging 1.036 percent copper. By the end of pyrite penrade all rocks within the zone, but 1960 more than 257 million tons of ore had been ore-grade copper mineralization occurs princi- mined, and about 2.4 million tons of copper pally along certain of the sedimentary horizons, had been produced from this ore body. The forming gentle to moderately steep-dipping tonna e and grade of present reserves are not tabular bodies-ranging from a few feet to availatle. However, exploration for new ore more than 200 feet in thickness. The ground bodies has continued, and reserves are estim4ted is intensely broken and is structurally com- to be adequate for many years operation at the plicated. Leaching and secondary enrichment current rate of production-approximately are contined to a thin layer at the top of the 100,000 tons of copper per year. Papago formation completely buried under New Cornelia Mine.-This Phelps Dodge alluvium and caliche. P 'te and chalcopyrite Corp. nine is at Ajo in the southwestern section are the predominant suld&. Molybdenite is of the State. Large scale mining operations sparsely and erratically distributed. Hydro- were started in 1917, when a 5,000-ton-perday thermally altered calcareous rocks, tactite, and leaching plant was completed. In !924 a hornfels contain the most copper. 5,000-ton-perday flotation plant wss bullt, and PRIMARY COPPER RESOURCES 49

additional plant facilities have since increased Chrysocolla (copper &cate) and the black processing capacity to more than 30,000 tons copper oxide, tenorite, are oxidation products of ore daily. occurring for a short distance below the bedrock The ore body is described as almost wholly surface. in monzonite porphyry, although the volcanic An open-pit mine was developed, and a 3,000- rocks to the southwest and southeast are also ton-perday concentrating plant was built. considerably mineralized. It is crudely ellipti- It began operating in 1957 on an ore body esti- cal in shape, about 3,600 feet long and 2,500 mated to contain 6,400,000 tons of approxi- feet wide. Its average thickness is 425 feet, mately 2 percent copper. In 1959 the rated and the maximum is about 1,000 feet. The daily capacity of the concentrator was increased primary mineralization is chiefly chalcopyrite to 4,000 tons. An agreement was made with with some bornite and a little pyrite. The neighboring Banner Mining Co. under which gangue consists of quartz and orthoclase, and Pima would enlarge its pit to include a certain the sulfides are distributed both in veinlets and portion of Banner property and would mine in grains scattered through the altered mon- and null 1.8 million tons of the Banner ore from zonite; the richest ore accompanies the more that area. A substantial tonnage of low-grade intensely altered rock. matenal is known to exist. The ore body was oxidized to a surprisingly The company plans to expand the open pit, level plane near the water table at an altitude eliminate the inclined skip, and provide for all of approximately 1,800 feet. Except for local truck haulage. The plans include increasing variations of as much as 50 feet, the transition mill capacity to 8,000 tons per day. from sulfide to oxidized zone was about as sharp Ray Mime.-This property of the Kennecott as could be mined by steam shovel. The depth Copper Corp. is about 80 miles east and slightly of oxidized ore ranged from 20 to 190 feet, south of Phoenix and about the same distance averaging 55 feet. Minerals of the oxidized north of Tucson in what is known as the Mineral ore were malachite with a little azurite, cuprite, Creek Mining District. Ore was mined by the tenorite, and chrysocolla. A little chalcocite block

1.68- ~ percent copper and returned 5,146 ounces ship, Gasp6 North County, in the Gasp6 Penin- gold. sula. 25 miles from the south shore of the Buchans ?dine.-This is in the central part GU~of St. Lawrence. of the island 3 miles north of Red Indian Two maior ore zones have been outlined on Lake and is operated ns the Buchans Unit of the comiany-owned property-the Needle 4merica.n Smelting and Rething Co. Geo- Mountain ore bodies and the Copper Mountain 56 COPPER ore body. The former consistg of bedded re- Sullico Mines, Ltd.-This property is in the placement deposits of chalcopyrite and pyrrho- township of Bourlamaque, 5 miles southeast tite, while the Copper Mountain ore body of Val d'Or. Two large sulfide replacement consists of late-sta e pyrite-chalcopyrite min- ore bodies occur in a series of siliceous volcanics eralization fillin ractures in a siliceous host which strike north 60 degrees and dip steeply rock. The Nee flBe Mountain ore bodies, where to the south. The ore has been localized in a most of the mining and development has been quartz-chlorite alteration zone that has been done, are higher in grade and more uniform in folded, fractured, and in places, replwed by the constitution than the Copper Mountain deposit. sulfides. The zone of alteration .has been The production schedule calls for 8,000 tons traced over a length of 1,500 feet, is 600 feet of ore per working day from the mine; 90 percent wide, and persists beyond the bottom level of is supplied from the underground operation, the mine. Ore bodies within the zone of and the remainder is from the open pit. The alteration have lengths of from 300 to 500 feet, ore reserve reported on January 1, 1960, was widths up to 95 feet, and ran e in vertical 63,710,000 tons, having a copper content of 1.29 height from 600 to 800 feet. %he principal percent. minerals are chalcopyrite, sphalerite, snd pyrite Quemont Mine.-This property of Quemont with small values in gold and silver. Mining Corporation, Ltd., is contiguous to, Mine production in 1959 was 2,600 tons per and directly north of, the Home mine of day from stopes above the 2,500-foot level. Noranda Mines, Ltd. The property lies within Seven levels are being developed below the the' city limits of the City of Noranda. Mine 2,500-foot level. The ore reserve reported and mill began production in June 1949 at its December 31, 1959, was 3 million tons- rated capacity (2,000 tpd); it has continued to averaging 1.0 percent copper, 0.73 percent produce at this or a slightly higher rate. zinc. and 0.008 ounce of eold and 0.35 ounce The ore bodies at the Quemont mine consist of silver per ton. - of sulfide replacements of a brecciated rhyolite, Normetal Minine Corooration. Ltd.-A and three types are mined: Massive sulfide re- copper-zinc that consists of 12 minkg placement ore; chloritized breccia ore, contain- claims in Desmeloizes Township, 13 mdes ing disseminated sulfides; and shattered breccia north of Dupuy station. Development and ore, containing sulfide stringers. The ore exploration of the mine has been accomplished occurs in a dome-shaped structure in which the by means of four shafts; three are in use today. permeable rhyolite breccia is the core, and a The ore bodies are massive sulfide replace- thick series of impermeable porphyritic rhyolite ment lenses in sheared rhyolite agglomerat,e forms the capping. Three main ore bodies which has been intruded by various igneous have been exploited, the West, the East, and rocks. Principal sulfide minerals in order of the Southwest. Exploration at depth is con- abundance are: Pyrite, sphalerite, chalcopyrite, templated to explore the ore zone. and pyrrhotite and minor amounts of galena, As of December 31, 1959, the ore reserves menopyrite, chalcocite, and bornite. Silver totaled 6,220,000 tons, containing 1.32 percent and gold are also found in the ore. The copper, 2.71 percent zinc, 0.176 ounce of gold sulfides are not evenly distributed in the ore per ton, md 1 .O6 ounces of silver per ton. bodies, since it appears that the copper values Waite Amulet Mine.--Owned and operated are concentrated along the ban ng wall sslde by the Waite Amulet Mines, Ltd., this is in while the massive pyrite and spr alente -. ,occur Duprat and Dufresnoy Townships, approxi- along the footwall. The ore body vanes in mately 9 miles north of Noranda.. length and width but on the 2,600 level shows The ore bodies occur as two types of massive a length of 1,025 feet and average width of sulfide lenses, lying along flow contacts in earlp 18.4 feet. Ore reserves as of December 31, Precambrian extrusives. The structure of the 1959, were reported as follows: region is complicated, and the structure localiz- zinc. ing the ore bodies is not easily recognized. The TOM %El prcm massive sulfide lenses consist of (1) pyrite and Copper-zinc ore...... 1,405,900 4 W 3. 22 sphalerite, containing 10 to 11 percent zinc Zinc re...... 192,800 --. 37 19. 00 and low copper; and (2) massive pyrrhotite Total....-.... 1,598,700 3. 59 5 05 lenses, carrying 4 to 7 percent copper and low zinc. Minor metals in the ore are lead, silver, Golden hlanitou Kine.-Operated by .Man- and gold. The ore reserve reported on Decem- itou-Barvue Mines, Ltd., this is in Bourlamaqu6 ber 31,1959, was 550,000 tons of approximately Township, Abitibi County, in northwestern 4.4 percent copper and 3.6 percent zinc. The Quebec, and consists of 48 claims wth an reserves have become deplebed, and mining will area of 1,850 acres. cease by the end of 1962; the company has been The ore bodies occur in sheared Keewatin absorbed by Noranda. volcanics which lie along the southern contact PRIMARY COPPER RESOURCE& 57 of the Bourlamaque batholith. The ore shoots folded after emplacement of the sill. Massive vary greatly in length and are from 6 to 60 feet stringers and lenses mineralized with chalcopy- wide. No definite bottom has been established rite, pyrite, and magnetite and minor amounts for the ore zone, which has been developed of pyrrhotite, gold, silver, and molybdenite down to the 2,950 level. The zinc ore bodies constitute the ore. Sulfide minerals also occur contain sphalerite, pyrite, menopyrite, chal- as fracture fillings and are disseminated in the copyrite, and galena, while the copper ore body wall rocks. The east-west veins have been is a mixture of chalcopyrite and pyrite, con- the most productive. Mineable widths range taining low but recoverable values in gold. from 3 to 73 feet; lengths are variable(t0 3,000 Ore reserves at the end of 1959 were: Copper feet);and the vertical extent is controlled by the ore (above the 1,870-foot level): 797,238 tons- contact between the gabbro sill and the under- averaging 1.14 percent copper, 0.25 ounce lying rhyolites; one zone was traced for a silver, and 0.017 ounce gold. Zinc ore (above vertical distance of 1,200 feet. the 3,000-foot level): 438,172 tons-averaging Reserves as of December 31, 1959, totaled 7.14 percent zinc, 0.98 percent lead, 5.63 5,278,700 tons of positive and indicated ore, ounces silver, and 0.03 ounce gold. averaging 2.97 percent copper. Campbell Chibongaman Mines, Ltd.-The mines are at Don5 Lake, Obalski Township, Ontario Abitibi-East County, in the Chibougamau The International Nickel Company of Canada, District of northwestern Quebec. In addition Ltd.-The original discovery of the Sudbury to the main property on Merrill Island, the District copper-nickel ores was made when the company owns the Cedar Bay property in Canadian Pacific Railway, building its trans- McKenzie Township, 6 miles from the mill, continental right+f-way, cut through a mineral- and has leased approximately 120 acres adjoin- ized outcrop near the present site,of the Murray ing the main mine from Merrill Island Mining Mine in 1883. Most of the Important ore Corp., Ltd. bodies were discovered within the next few The Merrill Island ore body, which extends years. southeastward into the property of Merrill The ore bodies in the Sudbury District are Island Mining Corp., Ltd., is localized along a associated with the norite member of the Sud- shear zone in altered and silicified anorthosite. bury irruptive. The contact of the norite with The shear zone ranges in width from 100 to 600 the underlying rocks is the primary stru,cture feet, is steep dipping, and has been traced for which determines the locat~onof ore depos~tlon. a strike length of 3,000 feet. The ore bodies Essential but secondary structures ye: Depres- occur in the shear as massive-sulfide replace- sions in the relatively smooth nocte footwall; ments with pyrrhotite, chalcopyrite, pyrite, shearing that roughly coinc~desmth the base and sphalerite-the principal minerals, occurring of the norite; contact breccia5 at the base of the in that order of abundance. The ore widths norite; and norite dykes or offsets penetrating average 40 feet but range from 12 to 85 feet. the footwall rocks. The,common ore minerals Contacts are radational, and the ore limits are pyrrhotite, pentlandite, and chalcopyrite. are determine% by assay boundaries. A new Minor amounts of cobalt, selenium, tellurium, ore occurrence has been encountered at depth and the platinum metals also occur in the ore. by diamond drilling, and an internal shaft is During 1959, the tonnage mined was ma~nly being sunk below the 1,900 level for exploration produced from underground operations at the of this zone. Proven and probable reserves as of June 30, five producing mines, FroodStobie, Creighton, 1959, totaled 10,191,134 tons, averaging 2.5 Garson, hvack, and Murray; the balance was percent copper and 0.068 ounce of gold per ton. produced from the Frood Open Pit. Thirteen Opemiska Copper Mines, Ltd.-At Chapais, operating shafts serve these mines for hoisting the company owns 58 claims in Levy Township, ore and handling men and supplies. Abitibi-East County, in the Chibougamau The ore reserve, reported December 31, 1960, District. The mine is serviced by three shafts. is as follows: Springer No. 1 shaft, 2,320 feet deep; Springer Nickel.coppcr No. 2, shaft, 2,414 feet deep; and Perry explora- Tons of ore: content, tom tion shaft, 2,000 feet deep. Springer No. 2 is 290,273,WO...... 8,715,300 the ore hoisting shaft. Mill capacity was expanded to 2,000 tons per day in November Falconbridge Nickel Mimes Ltd.-Iu 1928, 1959. Ventures, Ltd., acquired a group of claimsof the The ore bodies consist of veins localized in R Sudbury Basin and incorporated Falconbridge composite basic sill, intruded into acid and inter- Nickel Mines, Ltd., to develop the property. mediate voleanic rocks of Keewatin age, thc Additional property in the Sudbury area was whole assembly having been upturned and acquired in later years, and an active explora- 'PER toq program was maintained. New ore bodies ore to warrant bringing the mine into produc- were discovered and developed. tion, and shaft sinking started in 1956. The Underground operations are carried on at the mine plant and mill were completed in July Falconbridge, East, and McKim mines in the 1957, having a capacity of 800 tons per day. Falconbridge area on the south rim of the basin By the end of 1959 the shaft had reached a and at the Hardy, Boundary, Onaping, Fecunis depth of 1,562 feet, and mill capacity had been Lake, and Longvack mines in the Onaping area increased to 1,100 tons per day. on the north rim. AU these ore occurrences lie The Wilroy deposits occupy the same band of at or directly below the contact of the norite mehasediments in which the Geco ore bodies with the footwall rocks. Pyrrhotite, pentland- were found. Massive sulfides replace an iron ite, and chalcopyrite are the main ore minerals. formation to form a lenticular ore body which Ore reserves at December 31, 1959, were as strikes east-west, dips north at 70°, and follows: plunges east at 44". The ore consists of Ntckcl. Cw. TOM wrcenf wrcenf massive pyrite, pyrrhotite, sphalerite, magne- Developed ore: Falcon- tite, chalcopyrite, and galena. Zoning of the brid e, East, McKim, sulfides is apparent, and copper is more abundant ~a&,Onapin Fecun- in the center of the ore mass wbde sphalerite is Lake, and kngvark mines...... 22,200,050 1. 56 0. 87 predominates on the borden. Ore reserves on December 31, 1959, were: she,, Copper, .Z& mmca Tot...... 46,182,4 Tons: PIURL pcv ~on 2,708,066 ...... 1. 63 4. 85 1. 58 Qeco Mines, Ltd.-The property of Geco Mines, Ltd., 1 mile north of Manitouwadge Reserve figures allow for 10 percent dilution Lake in the Thunder Lake District, Port Arthur Mining Division of Ontario, consists of Manitoba-Saskatchewan 57 mining claims. Preliminary diamond drilling Flin Flon mine.-This mine of Hudson Bay indicated the presence of a sizeable copper-zinc Mining and Smelting Co., Ltd., second largest ore body and Geco Mines, Ltd., was incorporated copper producer in Canada, is on the border in October 1953 to explore and develop the of Manitoba and Saskatchewan 87 miles north property. The first ore was produced from of The Pas, Manitoba. an adit driven into the A zone in 1955. The Flin Flon deposit is in a sheared green- The Geco ore body occurs in a band of quartz stone-quartz porphyry complex. The lenticular sericite schist at the contact between the schist ore bodies are in a footwall and a hanging-wall and granite or garnetiferous hornblende-biotite zone separated by a band of barren schist as gneiss. Mineralization consists of pyrite, chal- much as 100 feet thick. The averagc dimen- copyrite, sphalerite, and pyrrhotite, with minor sions of the massive pyritic ore lenses are as amounts of gold and silver. A lenticular core much'as 900 feet long, 70 feet wide, and range of massive sphalerite-pyrrhotite mineralization from 1,500 to 2,500 feet in depth. Three types occurs close to and parallel with the south wall of ore occur in, the mine--massive sulfide; of the orebody. This core has a maximum disseminated pyr~teand chalcopyrite; and dm- thickness of 60 feet hut tends to lens out along seminated ore containing bands of massive sul- the strike and at depth. The high-grade zinc fides. The massive-sulfide type ore 1s charac- core is surrounded by a wide envelope of terized by sharp boundaries either against the disseminated sulfides including chalcopyrite, wall rock or agamst the disseminated ore. The sphalerite, pyrite and pyrrhotite. disseminated ore does not have a sharp cut-off, Ore reserves at the end of 1959 were as follows: and ore limits are established by assay bound- Szbcr, aries. Minerals present are pyrite, chalcopy- Copw, Zinc, ounce8 rite, galena, gold, and silver. The ore contams Ore body: TOM PCICC~~pmmf per tm A...... 3,016,300 1.94 1.93 1. 00 a small amount of arsenic, selenium, and cad- B ...... 7,098,400 1. 57 4. 51 1. 79 mium. Ore reserves December 31, 1959: C ...... 5,927, 800 2.38 5 33 3. 28 Odd. Sib. --- OUlCCd ancu Total ...... 16,042,500 1.94 4. 38 2. 19 Location: coppn. Zinr, per ~r At or near Tom pcrnnf pcrcel lo" fm These reserves allow for 10 percent dilution Flin Flon. 11,842,100 3. 12 3. 4 0. 066 0. 93 25 1,450 Near Snow and include ore to feet below the level. Lake ..... 5,615,500 1. 68 8 5 . 051 1. 13 Wilroy Mines, Ltd.-This company owns 30 mineral claims to the wkst of, and adjoining Lynn Lake Mine.-This property of Sherritt the property of, Geco Mines, Ltd. Diamond Gordon Mines, Ltd., was d~scoveredin Septem- drilling from the surface indicated sufficient ber 1941. Surface diamond drilling and under- PRIMARY COPPER RESOURCES 59 s ground exploration programs led to develop- has a maximum width of 2,000 feet, strike ment of two ore zones. The mine plants, the roughly north 70' west and has an average dip mill, and the branch line of the Canadian Na- of 70" to the south. Three distinct t pea of ore tional Railways were completed in 1953, and bodies occur at Britannia:,Large s&ceous re- production started in 1954. The Sherritt placement, containing dmeminated pyrite Gordon nickel refinery is at Fort Saskatchewan, chalcopyrite, and some sphalerite; stnnger- Alberta. The plant was completed in May 1954 lodes, containing chalcopyrite and pyrite; and with a designed yearly capacity of 16 8 million the barite-sphalerite type of zinc. pounds of nickel. Subsequent expansions have Ore reserve figures are not published, but it raised this yearly capacity, and in December is estimated that the reserve is sufficient to 1959 production was at the rate of 30 million maintain a 1,200 ton per day operation for at pounds of nickel a year. least five years. The ore bodies at Lynn Lake occur in faulted basic rocks which have been intruded as CUBA irregular stocks or plugs into Precambrian The major copper producer in Cuba is the metasediments and volcanics. These plugs- Matahambre mine in the Province of Pinar del consisting of varying amounts of diorite, gabbro, Rio, 100 miles west of Havana. Ore zones lie amphibolite, and noriteare numerous in the between, under, and sometimes in members of area but on1 two are known to contain ore four fault systems. The zones are tubular or bodies. Fading is common with the major pipelike, each containing many shoots occurring faults trending north and a secondary grou of as vein segments, lenses, and wedges. .Major faults striking northeasterly. Movement aP oug ore zones are elongated vertically, and con- the faults has caused shearing and brecciation, verging at depth they plunge generally toward and the ore minerals occur as bodies of massive the northwest. The ore minerals are chalcopy- sulfides, as disseminated sulfides, and as stock- rite and pyrite. Mill heads run 6 percent; a works of sulfide stringers in the fractured zones. 32 Dercent comer concentrate is produced with The two principal ore bodies are the A and the 9'8 percent ;&very. EL. The A ore body contains 4,975,000 tons, In 1957 daily production was curtailed from averaging 1.22 percent nickel and 0.64 percent 1,100 tons pe; day to 700 tons per day and copper, and is a disseminated-sulfide type. The annual output of copper has declined from EL ore body has massive-s&de mineralization 20,000 tons in 1955 to 10,000 tons in 1959. and stockworks of sulfide stringers fillmg Reserves are not known but the company is fractured zones in the basic rock. Combined optimistic about encountering a sizeable ore tonnage and rade of the two types of ore, in body at depth. the EL ore bo f y totals 2,445,000 tons, averagmg 2.50 percent nickel and 0.93 percent copper, The copper precipitate recovered at the nickel refinery is shipped to Noranda, Quebec, or Consolidated Halliwell, Ltd., of Canada holds Tacoma, Wash., for smeltin Production in title to a 100-square-mile-minin concession, 1959 was 12,406 tons of nicfel, 5,171 tons of through its Haitian subsidiary, E edren, S.A., copper and 314,343 ounds of cobalt. Ore in the northwestern, part of the Republic of reserves at the end of' 1959 were reported as Haiti. The district is known as Terre-Neuve, 14,158,000 tons, averaging 0.96 percent mckel and is 180 miles north of the capital, Port-au- and 0.54 percent copper. Prince, and 13 miles from tidewater at Gonaives. Almost 81,000 feet of diamond drilling was British Columbia completed at the Meme, Caaseus, and Brasillac The Britannia mine, of the Howe Sound Co. showings, including 11,290 feet of underground is on the east side of Howe Sound, a proxi- drilling in the main Meme workings. Two mately 30 miles north of Vancouver, an8. is one distinct types of ore have been explored, surface of the oldest and largest base-metal mines in secondary oxides and underground primary Canada. From 1939 through 1957 mine pro- sulfides. duction averaged about 4,200 tons of ore per The surface-oxide mineralization occun as day; then the property closed early in 1958 rich pockets of erratic distribution which are because of low base-metal prices. It was easily accessible and appear limited in tonnage. reopened in January 1959 and operated for the balance of the year at an average rate of 1,200 The copper minerals are entirely oxides and tons a day. carbonates, principally malachite and azurite. The ore bodies occur in a northwesterly The primary ore is entirely beneath the surface trendin shear zone in a roof pendant imbedded and contains chalcopyrite and bornite in nearly in the oast Ran e batholith. The shear zone equal proportions, with minor chalcocite in has been" traced or a distance of eight miles, local instances. The principal gangue minerals 60 COPPER are epidote, garnet, calcite magnetite, chlorite, recent years chalcocite has supplemented the and quartz. native metal as the principal mineral in the At 30 cents per pound for copper, ore reserves ores. The deposits are found in beds of two after dilution have been estimated at 4,031,400 unconformable clastic formations known as the tons, averaging 1.88 percent copper. Ramos and Vetas. The Ramos beds dip east- ward while the Vetas dip westward, and they are separated locally by the steep dipping A little more than half of Mexican copper Corocoro fault. Native copper is localized in production comes from copper ore deposits, certain sandstone beds of the Ramos and in the and the balance is recovered from complex oxidized zone of the Vetas. Throughout the lead-zinc-copper ores. Reserves of copper ore Vetas chalcocite is interstitial with sand grains are not well known for Mexico; however, under and rock fragments in certain red sandstone favorable economic conditions most of the large and arkose beds. The localization of chalcocite mines apparently have ample reserves in a particular bed seems related to processes of sedimentation. Operat?to supp y continuing operations at present production rates. It is estimated that approximately 7 million Cananea Consolidated Copper Co., S.A.- tons of ore, containing 350,000 tons of copper, This subsidiary of Greene Cananea Copper Co., have been taken from the district. A reserve owned by The Anaconda Company, operates of 750,000 tons of 2.6 percent copper ore was underground and open-pit mines, a concentra- estimated in 1957. tor, and a smelter near Cananea, Sonora, 50 Chacarilla Copper fie.-This mine 90 miles miles southwest of Bisbee, Ariz. southwest of LaPaz, is being developed by six The ore bodies are relatively homogeneous Japanese wmpanies. The reserve has been deposits, occurring in breccia pipes associated estimated at 900,000 tons of 4 percent. copper with porphyry and granite intrusives. The ore, and if development is successful a monthly mineralized pi ex occur in an area 6 miles wide production of 700 to 1,000 tons of ore is sched- and 15 miles Eng. The prmcipal ore mineral uled. The concentrates will be shipped to is chalcocite; the ore gangue is an intensely Japan. siliceous, kaolinized, sericitized, fine-textured volcanic rock. The ore bodies are limited by CHILE assay bundaries. The copper mining industry of Chile consists Ore reserves are believed to be large at the of three sectors: American great mining corn- present operating grade of 0.7 to 0.8 percent panies, medium mining com anies, and small copper, but they are not blocked out in advance copper-mining compames. '!he great minlng of requirements. Production in 1959 was enterprises are those producing 25,000 tons or 32,182 tons of copper, 433,771 ounces of silver, more of copper per year. At present there are and 9,030 ounces of gold. three companies in this category; Chile Ex- Boleo Mine.-This Lower California mine ploration Co., Chuquicamata mme; Andes was operated by Compagnie du Boleo from 1886 Copper Co., El Salvador mine; and Braden until 1954. Compagnie Minera Santa Rosalie, Copper Co., El Teniente mine. Medlum S.A., a semio5cml agency of the Mexican mining companies produce less than 25,000 Government, is conducting studies to develop tons of wpper annually but have cap~tal,of low-cost methods to concentrate and smelt com- more than 15 million pesos. Small mu1111 plex low-grade copper or? from numerous but companies are firms or indimduals with capitaK small occurrences m the district. The ore series not greater than 15 million pesos. The great includes three beds of conglomerate averaging mining companies account for about 90 percent 100 feet in thickness. The ore minerals are of Chilean copper output, and the balance is principally chalcocite with minor bornite and divided between the medium and small pro- chalcopyrite. Reserve information is not avail- ducers. able, however, there apparently is enough ore Chuquicamata, 160 miles northeast of the in the area to encourage continuing research on port of Antofagasta by rail, is considered to be economical recovery methods. the largest economic copper deposit in the world. It is owned by the Chile Exploration South America Co., which is controlled by the Chile Copper BOLIVIA Co., a subsidiary of The Anaconda Company. The mine lies at an altitude of 9,300 feet in the Corocoro Mine.--Operated by the Bolivian northeastern part of the Atacama Desert, one Government, it is of unusual interest because of of the most arid regions in the wofld. Because the presence of native copper that constituted of the extreme aridity, large quantities of sulfate much of the production for many years. In and other water-soluble minerals have accumu- PRIMARY COPPER RESOURC~ 61 lated that normally would have been carried widespread metal wning. The ore body is a away by rainfall. wne of secondary enrichment that ranges in The deposit is a pear-shaped porphyry mass thickness from a .few feet at the edges to more about 2 miles long, 3,600 feet wide, and with .than 950 feet in its central rtion. Chalwcite unknown depth. It is in the midst of a large is the rincipal ore mineray body made up ofcpdior,ite and monzonite Bloc5 cavmg is the mining method used, and porphyry. Mmer zation IS related to ex- the mine has capacity to produce 24,000 tons tensive fracturing and shearing,, acwmpanied of ore per day. The average grade of ore is by much silicification and sencit~zation,and 1.5 oercent comer. and the reserve is estimated occurs in veins and innumerable networks of at fi5 millionLtbns. veinlets. The ore body contains three types. la Africana Mine.+erated by the Santia Oxide ore occurs in the upper section and has Mining Co., a subsidiary of The Anacon f'a averaged 1.63 percent cppper. Below ,the Company, this is 15 miles west of Santiago horizon of oxide ore there is an area of mlxed at an altitude of about 3,000 feet. Produc- ore lying above the huge reserve of sulfide ore, tion started in 1957. Ex~ansionof mill facil- averaging slightly less than 2.00 percent copper. ities has increased annual production capcity to The principal oxide mineral is antlerite, 6,000 tons of wpper in the form of concentrates. Cua(SO,)(OH),, and the most important mmor The ore body is a fault fissure 10 to 60 feet oxide minerals are atacamite, brochantite, wide in wastal grandiorite batholith of Cre- chalcanthite, and krohnkite. The sulfide min- taceous Age. The oxidized-leached zone erals in the upper part of the sulfide zone are reaches a depth of 160 feet; below is a zone of mainly chalwcite and covellite; enargite is secondary enrichment 30 to 100 feet in depth, found at increasing depth. assaying 6 to 12 percent wpper with chalwcite Approximately 190,000 tons of ore and waste being the chief mineral. In the primary ore is mined daily. The annual output of the zone the principal wpper mineral is chalwpy- sulfide plant and the oxide plant is 300,000 tons rite. Ore mmed averages 3.2 percent wpper of wpper. At this rated capacity roven ore from which a 29-percent copper concentrate is reserves at Chuquicamata are s cient for produced. Ore reserves are estimated at 2.5 more than 50 years. From the start of opera- million tons, averaging 3.5 percent copper. tions in 1915 through December 1959 Chuqui- Braden or El Teniente Mine.-Braden Cop- roduced 6,835,000 tons of copper; er Co., a subddiary of Ke~ecottCop er camata1959 pro $uction . totaled 306,500 tons, a record &orp., owns this mine, in the Chilean An fes output. 7,000 feet above sea level at the town of sewell: El Salvador fie.-This mine of Andes 80 miles southeast of Santiago. Copper Mig Co., a subsidiary of The The Braden deposit is unique among first Anaconda Company, is a major porphyq w rankin copper producers of the world for being er deposit in the great w,pper belt of t t e- locatefin and around an old explosive volcanic bilean Andes. The mine is in Atacama Pmv- vent. Only underground mimng has been ince, 65 miles inland from the Pacific port of practiced, and only sulfide ore has been treated. Chanaral and 20 miles north of Potrerillos. Molybdenum is recovered. Annual produc- Production that was started in April 1959 re- tion of copper is between 180,000 and 190,000 aces that of the old mine and concentrator at tons. Mine production in 1960 was 11.5 $otrerillos which diswntinued operations million tons of ore, averaging 1.95 percent June 10, 1959. The mine, concentrator, and copper. In 1947 reserves were estmated at smelter were designed for copper production of 200 million tons of 2.18 percent cap er 100,000 tons per year; production in 1960 was Medium and Small Mines.-Of t!e medium 87,000 tons. and small mining companies, 10 account for A broad band of intrusive rhyolite dikes and about 60 percent of the production of ths sheets and monzonite porphyry extends for group. The nlne long established firms in this several miles to the southwest of Indio Muerto pu are Cia. Minera TocopiUa, Cia. Minera Peak, making a major structural axis along du h"&ta, Cia. Minera Disputada, Cia. which the El Salvador center of intrusion and Minera Cerro Negro, Cia. Minera Tamaya, mineralization occurs. Mineralizing dctivity Cia. Minera Aysen, Sali Hochscbild, Renaci- along th~saxis 1s in a belt 3 miles long and 1 miento Aurifero, and Capote Aurifero. The mile wide. Within the zone several centers loth, the Santiago Mining Co. La Africana of better-grade wpper mineralization and more mine, started production in 1957. intense alteration are localized by intrusive Two other important wpper deposits have rocks. El Salvador is in the southernmost and been developed and are nearing the product~on largest of these centers. Occasional small, stage. The Cerro de Pasco Corp. has been scattered argentiferous lead-zinc velnlets fring- engaged in an exploration program on the Rio ing the wpper mineralization indicate weak, Blanw copper property, 35 des northeast of 62 COPPER Santiago, since 1955. Reserves of 121 million economic concentrations, of co per silver ore, tons of ore, averaging 1.6 percent copper, have silver ore, and lead-zinc siger -ore. The been delineated, and the company is studying copper ore bodies vary greatly in size, and few the economic feasibility of the project. An persist more than 300 feet vertically. Enargite- 11,000-ton-perday block caving operation is famatinite, luzonite, and tetrahedrite-tennant- planned. The next step will be driving a 3- ite are the usual ore minerals but bornite, mile adit under the ore body from which further chalwcite, and chalcopyrite dominate in localized exploration and development of the ore body occurrences. Vein mineralization accounts for can be wnducted at depth. about half the ore tonnage. Some veins follow The Empressa Minera de Mantos Blancos, a fractures within the pyrite mass, and others ex- subsidiary of the Mauricio Hochschild organi- tend for hundreds of feet west into the volcanic zation, has explored and developed the Mantos rocks of the vent. Most of the copper and Blancos deposit, 28 miles east of Antofagasta zinc in the mantle of oxidized material, known at an elevation of about 3,000 feet. Drilling locally as pacos, were leached-except in small since 1952 has proven the first 10,500,000 tons areas adjacent to the limestone where these of about 2 percent copper ore. The several ore metals occur as carbonates. Rich secondary bodies lie within an area 2.5 miles long by 1,640 sulfide ores, chalwcite, and covellite extended feet wide and extend in depth below 164 feet; below the pacos 500 feet to the primary pyrite many of the drill holes are bottomed in ore. material; mining today is limited to primary The mineralization consists of copper oxides- ores. mainly the copper oxychloride, atacamite. Morococha.-Deposits, mined by Cerro de The leaching plant was officially inaugurated Pasco Corp., a subsidiary of Cerro Corp., are March 27, 1961. The annual capacities of the about 100 miles east of Lima at an altitude of open-pit mine and leaching plant were designed 14,500 feet. They are of several types: (1) for producing 18,000 tons of fire-refined copper. Fissure veins in altered limestone, volcanic rocks, and quartz-monzonite; (2) limestone re- PERU placement mantos, pipes, and sills; and (3) Until 1960 the Cerro de Pasco Corp. was th2 contact metamorphic wnes adjacent to the principal producer of copper in Peru. The intrusion. Mineral and metal zoning is well corporation operates copper-producing mines exhibited at Morococha, both on a horizontal at Cerro de Pasco, Morococha, Yauricocha, or district pattern and on a vertical scale in the and the recently reopenedSan Crist6bal mine; separats ore bodies. Enargite in the central concentration plants located at Cerro de Pasco, zone gives way to chalcopyrite and bornite in Casapalca, Morococha, and Mahr Tunnel; and the surrounding limestone. Reserves are un- a smelter at Oroya. Northern Peru Mining known but are understood to have decreased Co., a subsidiary of the American Smelting and in recent years. Refining Co., produces copper from ita Quiru- Yauricocha fie.-This mine of Cerro de vilca mine. Other copper producers include Pasco Corp. is in the Department of Lima, several Peruvian-owned organizations, operating Province of Yauyos. High-grade sulfide ores mines and concentration plants, and the French- in steeply dipping irregular mantos in limestone owned Campagnie des Mines de Huaron. In and an extraordinary pipe of rich oxidized ore, addition, small copper mines, mainly Peruvian- all carrying silver and gold as well as copper, owned, sell their ores to the principal producers comprise the valuable deposits. The ore bodies or other ore buyers for processing or export. are replacements in limestone adjacent to and In 1960 Peru advanced to one of the major probably genetically related to a stock of mon- copper-producing countries of the world when wnite porphyry. The principal ore mineral is more than 145,000 tons was recovered from enargite. Only direct smelting ore is mined; the Toquepala mine of Southern Peru Copper the grade of ore shipped in 1959 was 5.8 percent Corp. The Quellaveco, Cuajone, Antamina, copper, 1.2 percent lead, 2.3 percent zinc, and and Cobriza deposits have been explored and 4.5 ounces of silver per ton. Reserves have contain large reserves of low-grade ore. been estimated at about 700,000 tons of ore. Cerro de Pasco.-Deposits are localized in San Cristoba1.-The deposit, in the Depart- and around the eastern and southern portion ment of Junin, mined by Cerro de Pasw Corp., of a body of pyroclastic rock, agglomerate, consists of fissure vein systems of zinc-lead- and quartz-monzonite porphyry that appears copper-silver ore. Ore extensions found in the to be a deeply eroded volcanic vent. A large early 1950's replenished depleted reserves. In cresent-shaped replacement mass of pyrite and 1960 the mine was reported to have 1.5 million silica is contained in the contact zone between tons of measured ore-averaging 1.2 percent the volcanic rocks of the vent and the lime- copper, 9 percent lead, and 12 percent zinc stone east of the major fault. At intervals Sphalerite is the dominant ore mineral mthin within the massive pyrite body are found the mine area and chalcopyrite is next, but PRIMARY COPPER RESOURCES 63 silver, lead, and gold contributed about half circular in plan and about 3,000 feet in diameter the total value. near the surface. With depth the ore body Quirnvi1ca.-This mine of Northern Peru divides into two distinct roots; the northern Mining Co., a subsidiary of American Smelting portion tapers downward as an inverted cone; and Refining Co., is in the Province of Santiago and the southern portion follows down the south de Chuco, in the Department of Liberstad, contact zone of the quartz-monzonite intrusive. about 80 miles from the port of Salaverry at an Sulfides withm the ore body occur as small vein- altitude of 13,000 feet. The copper veins occur lets that may be aa much as 2.5 inches wide in a small portion of a large mmeralized area but are usually 0.5 inch wide, or less, in closely withm which there is considerable diversification spaced array. Pyrite k the most abundant of in the- content of the veins. There are three the sulfide minerals; chalcopyrite is the princi- mineralized areas in, the larger ,district-a pal ore mineral. Minor quantities of bornite, southern group of sdver veins w~thquartz galena, sphalerite, and enar ite were noted in Umg, a central group of enargite and tetra- the drill samples. ~olybfeniteis common hedrite veins, ,and a northwesterly group of. hut spotty. Supergene enrichment processes silver veins mth barite gangue. Operations have formed chalcodte and covellite. Oxide have been centered largely on the copper ,group. minerals and local concentrations of native Those copper ,veins are potable for then per- copper occur where the zone of oxidation en- sistence in str~keand nuneralization, and the croaches upon enriched ore. Reserves have ore averages more than 5 percmt copper. been estimated at 500 million tons of slightly Copper production ranges between 5,000 and more than 1.1 percent copper ore. 6,000 tons a year. Reserves are unknown. Quellaveco.-The deposit is the smallest of Toquepala.-This Southern Peru Copper the three having an estimated reserve of 200 Corp. mine is in southern Peru, 55 airline miles million tons of ore of approximately the same north of the small city of Tacna and the same grade as the other two. distance inland from the port of 110. The Antamina.--This deposit, approximately 100 Toquepala ore body lies in a mineralized zone, miles northwest of the town of Cerro de Pasco, elliptical in shape and about two miles long, has an indicated ore body of approximatsly which has been the locus of intense igneous 100 million tons of 1.5 percent copper ore. activity. Several small intrusive bodies having Exploration and development activities by irregular forms occur within and adjacent to a Cerro de Pasco Corp. at thls deposit were centrally located large breccia pipe. The temporarily suspended in 1957. mushmm-shaped ore body consists of a flat- lying enriched zone of predominant chalcocite Cobriza.-The deposit, 115 miles southwest with a stemlike extension of hypogene chal- of La Oroya, was explored by the Cerro de copyrite ore in depth within and around the Pasco Corp., and the tonnage of 3.5 percent pipe. Hydrothermal alteration is perpssive in copper ore developed in 1961 would support the zone. The principal sulfides, qyr~te,chal- mining for an annual production of approxi- copyrite, and chalcocite, occur malnly as vug mately 9,000 tons of copper in concentrates fillings in the breccia, and aa small grains for about 10 years. scattered through all the altered rocks. Operations at Toquepala of the Southern Europe Peru Co per Corp. began January 1, 1960, and AUSTRIA the schea uled rate of production was reached m March. Mine production of ore and waste The Mitterberg mine, near Salzhurg, is the averaged 166,897 tons per day. Ore milled most important of 22 copper mines listed for averaged 26,052 tons per day and contained Austria. Two others, the Schwaz and the 1.73 percent copper, which is substantially Untersulzhach, are intermittent producers but higher than the average grade of the ore body. only Mitterberg operates continuously. It According to published data the deposit csn- has been known as an Important source of tains 400 million tons of open-pit ore, averaging copper since ancient times. The ore averages a little more than 1 percent copper. Production 1.6 percent copper and occurs in veins with in 1960 was 145,115 tons of blister copper. siderite, andesite, and calcite ag. matrix; chalco- Cuajone.-This porphyry copper deposit is pyrite is the principal ore nuneral. The re- the northernmost of a group of three deposits serve is estimated at 3 million tons of ore, in southern Peru controlled by the Southern averaging 2 percent copper. Peru Copper Corp.-Toquepala, Quellaveco, and Cuajone--all within a 20-mile belt. The BULGARIA principal ore body, the Chuntacala, is on the Bulgaria has more than doubled its produc- southern part of the ,northeastwarddipping tion of electrolytic copper in the last five years. Cuajone quartz-monwnite stock. It is roughly Recently discovered deposits at Panagyurlste, 64 COPPER in the Stara Planina mountains, and near ore that year; 4,742 tons of nickel concentrate Malko Turnovo provide sources for further and 390 tons of copper concentrate were expansion of mine capacity. The lead-zinc recovered. ores of the Rhodopt region have important Fyhasa1mi.-This deposit in the Province of copper values. Information regarding produc- Onlu has been developed for an annual pmduc- tion, reserves, and descriptions of the operating tion rate of 600,000 tons of ore; the expected copper mines is not available. It is known recovery of copper, beginning in 1962, is 16,500 that smelting and electrolytic relining capacities tons. The deposit contains copper, zinc, py- are being increased and a large expansion of rite, and precious metals. Bulgarian copper production is planned for 1962. Refinery output was 14,000 tons of EAST GEFMANY electrolytic copper in 1960. Most of the German copper has come from FINLAND the Mansfeld area. The ore body is a thin but extensive cuprifemus bed of black shale, 0utokumpu.-This mine is in eastern Fin- 30 to 40 centimeters thick, which contains land, in the Province of North Karelia, about as much as 2 percent copper. Comprehensive 30 miles northwest of the town of Joensuu. exploration m the Sangerhausen basin devel- The massive sulfide ore deposit, about 3,800 oped a 35-centimetwthick copper-slate dcposit, meters long, 300 to 350 meters wide, and 7 to 9 having higher copper content than that of the meters thick, is part of a beltlike complex ef Mansfeld basin Copper production will shift quartzite and serpentine rocks. The ore min- from the Mansfeld to the Sangerhausen area as erals are chalcop , pyrite, and pyrrhotite; the newly developed Niedermeblingcn copper the average meta yntecontent of the ore is 3.7 per- mine reaches the planned production rate. As cent copper. Reserves are estimated at about a consequence copper production of East 15 million tons. Germany is expected to be 70 percent higher Paronen.-The mine is in the Parish of in 1965 than in 1958 or about 41,000 tons. Ylojiirvi about 12 miles northwest of the town of Tampere. In the area the rocks afe mainly IRELAND volcanics which are strongly broken m places, forming two almost parallel breccia zones. The Avoca Mine.-This property of St. Patrick's ore deposit forms part of the larger zone, and Copper Mines, Ltd., is 43 miles south of Dublin the breccia differs considerablv from the sur- and 7 miles from the small harbor of Arklow. rounding volcanics. The angdar fragments of The outcrops in the area were first worked discolored tuffite and porphyrite have been many centuries ago, but the earhest under- cemented by a mass of ore-bearing, fine-grained, ground mining was in the 1750's. Mining was needlelike tourmaline. Chalcopyrite and me- carried on continuously until around 1880. nopyrite occur in var ing amounts, and com- Forkings in a strike length of about 3 miles, mercial ore bodies are zkely to be limited, often having more than 100 abandoned shafts as irregular in form, and without any definite much as 700 feet deep, indicate the intensity of geological contacts. The ore is low grade, historical mining activity. containing about one percent cop er, minor The ore bodies are sulfide-rich sheets, lenses, amounts of silver and gold, and in p f' aces about and associated tonguelike zones lying within 0.1 percent tungsten trioxide (WO,). The ore altered schistose rocks. The ore minerals in reserve is estimated at 1 ,million tons. order of abundance are: Pynte, chalcopyrite, Vihanti mine.-This 1s a proximately 30 sphalerite, and galena. Reserves of about 20 miles south of the town of 0uTu on the Gnlf of million tons of ore, assaying 0.95 to 1.36 percent Bothnia. The ore bodies are located in a copper, have been developed. schist zone where the main rocks are mica Mountain Mine.-Near Allihies in County schist, quartzite, and marblethe latter largely Cork, this is being developed by Can-Erin altered to a skarn. Mineralization occurs in at Mines, Ltd., of Canada. Limited drilling has least two separate and parallel zones in an area proved a totalof 2,350,000 tons of ore, averaging which is about 4,000 feet long and 650 feet wide. about 2 percent copper. Sphalerite is the most abundant ore mineral, galena and chalcopyrite occurring as a weak NORWAY dissemination throughout the ore. Accessory The cupriferous iron pyrites mine of Orkla minerals are cubanite, tetrahedrite, and ten- Grube-Aktiebolag is at Medalen. De osits are nantite. Cop er production in 1959 was 3,227 massive pyrite lenses in gabbro anB contain tons containerfin concentrates. about 2 percent copper. Smelting and refinmg Kota1ahti.-Thls mine, in the center of plants at Thamshamn in Orkedalsfjorden are Finland south of Jyvkkyla, started operations operated by Orkla Metal-Aktieselskap, a sub- in October 1959 and produced 40,652 tons of sidiary; the head office is in Lokken Verk. In PRIMAFLY COPPER RESOURCES 65 1959, 342,303 metric tons of ore was mined of methods. Cop er is recovered from the ore which 245,616 tons was smelted, yielding 3,800 by leaching ani cementation; by direct smelt- tons of copper and 78,349 tons of sulfur. The ing to produce a copper matte and sulfur dioxide ore reserve in mid-1959 was estimated to be for making sulfuric acid; and by flotation sdicient for about 15 years production. followed by smelting. Reserves in 1958 were The other principal producer of copper in estimated at 4.5 million tons of copper (content Norway is Suhtjelma Gruber, A/S, which o er of ore). ated cupriferous pyrite mines at ~ulitjeki about 60 miles east of Bod& The ore. in lenses. SWEDEN consists of copper-bearing pyrite and hhotite; Most copper mining in Sweden is carried on disseminated tbrounh mica schis~. Some of the by the Boliden Mining Co., which operates pyrite is massive. -Copper production in 1958 several mines in a 200-mile strip from the Gulf was approximately 3,800 metric tons. Ore of Bothnia in the east to the Lapland mountains reserve data are not known. in the west. The mines are grouped into four POLAND distinct areas near Boliden, Kristineberg, Adak, and Laisvd. There are three mines in the The princi a1 ca per-minmg districts are the Boliden area-Boliden, Renstrem, and Lkngsele. Zootoria an: ~of&twiec-~rodziecbasins- Kristineberg is 60 ,miles west; Ravliden, a estimated to contain 200 million tons of ore, small producer, is 3 miles further west. The averaging approximately 0.7 percent copper. Adak district, 80 miles northwest of Boliden Production in 1957 came from three mines, the has two producing mines, the Adak and Rudtje- Konrad, Lubichow, and the Leona and backen. These are State owned but o erated amounted to 1,256,000 tons of ore, containing by the Boliden companv. Tne ~aisv&mine 0.61 percent copper. Full capacity of these is 140 miles west of Bolide?, near the Lapland three mines is scheduled for an annual output mountains where lead-beann ore is mined. of 2.5 million tons of ore. The 1960 annual The three areas of Bolif en, Kristineberg, rate of copper production was about 10,000 tons. and Adak comprise the Skellefte District with Exploration revealed new reserves in the mineralization occurring in Precambrian rocks. Lublin-Gtog6w area in Lower Siesia, and de- The principal ore bodies are massive sulfide velopment of three mines in this area will start ores-the most common being compact p+te in the next five years. The first ore is expected with subordinate pyrrhotite, chalcopyrite, from the Lublm mine in 1964 with production sphalerite, and galena in varying amounts. on an industrial scale scheduled for 1966. Some of the ore bodies are in drag folds, while Development of the Polkowice I will start in others are in shear wnes or at the junction 1963 and at the Polkowice I1 in 1965. These between bedding and shear zones. The dips three mines will be in full production in the of the ore bodies are generally steep and the 1970's. The smelter and refinery planned to wall rocks are mostly sericitic or chlontic schist. treat the Giog6w ore will be put into operation A11 the mines are small producers, working at by 1968-70. shallow depths. In 1958 reserves were estimated Deposits near Glog6w are of the sedimentary at approximately 70 million toos or sdcient type in an area of about 200 square kilometers, to insure 40 years production at present containing an estimated reserve of about 10 capacity. million tons of copper. The average copper content of the ore has been estimated between U.S.S.R. 1.4 and 2.0 percent. Principal copper deposits occur in five general areas, Kazakhstan, the Urals, Uzbek- istan, Noril'sk, and Armenia. Quantitative The copper-bearing massive ppite deposits data showing total copper productlon of the in southern Spain have been worked for more U.S.S.R. or any of its regions are not available. than 3,000 years and have been an important However, annual percentage increases to 1955 suuree of copper and pyrite since Roman times. and results of the Fifth Five Year Plan have The most important roducer is the Compania been published. This information formed the Espanola de Minas fIe Rio Tinto, formerly a basis for developing production data in tonnage. British company, but now controlled by the Annual copper production increased 25 percent Spanish overnment. The Rio Tinto mining between 1955 and 1959 (from 385,000 to area is a% out 37 miles north of the port of 480,000 tons), and the U.S.S.R. Seven Year Huelva in Huelva Province and accounts for Plan (195945) proposes to almost double more than 90 percent of the output of copper 1959 production by 1965. The copper cpntent from Spanish mines. Cnpreaus pyrite is mined of reserves in the Soviet Union was estlmated by surface (open cast) and underground to have been about 35 million tons at the 66 COPPER beginning of 1959. A reserre god approaching seminations and veinlets in peridotite to form 45 million tons by 1965 is anticipated in the 1- to 3-percent wpper ore, carrying 0.5 percent Seven Year Plan. The quality of the reserves nickel and some of the platinum group metals. are not known and they may include low- In Armenia w per ore is mined on a small grade protore uneconomical to mine at present scale at four loc&es, Akhtala-Shamlug, Das- values. takert, Kadzharan, and Kafan. Copper re- Kazakhstan, accounting for more than half serves in the Caucasus although lowgrade are of the U.S.S.R. output of cop er ore, has extensive (600,000 to 1,200,000 tons wpper producing mines in three areas, 6zhezkazgan- content). Karsakpay, Balkhash-Kounradskiy, and the In Northern Karelia and the Kola Peninsula Altai in East Kazakhstan. The Dzhezkazgan are signi6cant deposits of copper-nGkel ore deposits are copper-impregnated sandstones, containing cobalt and platinum group metals. of the Rhodesian type, fomng gently dipping Reserves in central Asian U.S.S.R. are lodes extending outward from feeder faults. important. The largest at Alrnalyk, 56 miles The ore averages 1.62 percent copper and southwest of Tashkent is reported to have a contains chalcopyrite, bornite, and chalcocite copper content of 3 million tons. as the principd ore minerals. The most recent reserve estimate of 3.5 million tons of wpper YUGOSLAVIA content is now considered too modest. The Bor Mine.-Situated about 75 miles from porphyry copper-type deposits in the Balkhash- Belgrade, this is the principal source of cop er Kounradskiy area are extensive and low grade. in Yugoslavia. Annual production of the I! or They consist of disseminated ellow sulfides and mine is about 30,000 tons of wpper, scheduling supergene chalcocite in smal9 porphyry masses operations at 4,000 tons per day of 1.8 percent and invaded rocks; small quantit~esof molyb- copper ore and 500 tons per day of 5 to 6 percent denum, gold, and silver are also present. The wpper ore. The im rtant deposit? at Bor shallow enriched zones, averaging about 1 are three massive be8 ike ore bodies ~naltered ercent wpper can be economidly mined. andesite porphyry. The largest wntains py- $he cop er content of reserves in the region rite and enargite, with minor amounts of estimate $ at 2 million tons are believed to in- luzonite and famatmite. The ore, enr~chedby elude areas of protore carrying only 0.5 to 0.7 secondary chalcocite and wvellite, carries percent copper. In the Altai region of eastern from 5 to 6 percent copper and some gold. Kazakhstan, a major lead-zinc center, wmplex The second ore body also yields 5 to 6 percent ores contain recoverable copper. Other main copy ore, and the third contains pyrite and deposits in Kazakhstan are at Bozshakul' and cha copyrite mth a wpper content of 1 to 2 Uspenkiy. percent. The princi a1 co per mines in the Urals are Majdanpek Mine.-In the eastern part of at ~rasnouray'sk,&rovgrad, Degtyarsk, Kara- Yugoslavia, this is actually in the northeastern bash, Sibay, and Blyava. Copper-bearing part of the Republic of Serbia. It is about 75 pyritic lodes yield most of the wpper ores mined miles from Belgrade, 9 miles from the Danube, in th~sregion. The wpper content of the ore and 25 miles north of the Bor mine. Explora- is less than 3 uercent, but it also wntains ex- tion by the Yugoslavian Government in 1949 tractable quaitities of zinc and has values in led to the develo ment of extensive wpper ore gold and selenium. In 1950 the total reserve in deposits at Maj 5' anpek, which is one of the the Urals was estimated at 4 million tons of oldest mining districts in Yugoslavia, havl?g wpper contained in 246 million tons of ore. about 2,000 yean of mining history. This There are low-grade copper deposits in the copper-bearing area is in the most northefn western foothills of the Urals and in the Donets part of the andesite mass of East Serbm. Basin that have not been developed. The Gay Magnetite, pyrite, and chalcopyrite occur. as (section of Orsk) deposits discovered in 1958 either fine disseminations or as irregular .veins. contain five ore bodies having values in copper Chalcopyrite is the principal copper ore mineral. and zinc sulfides. Two of the ore bodies (1 and Ore reserves of the Bor-Majdanpek combme 3) now being developed average 4 percent have been estimated at 275 million tons aver- copper; in some sectors the ores are 11 to 12 aging about one percent wpper; Majdanpek percent, and samples assaying 30 percent wpper accounted for 221 million tons, wntainmg an have been reported. average of 0.824 percent copper. The Noril'sk district is east of the lowlands The Majdanpek mine is ex ected to produce of the Yenisey River and borders the north- 12,000 tons of ore per day k' or a recovery of western section of the .Siberian massif. Mag- 25,000 tons of wpper annually. When the matic copper-nickel deposits occur as intrusive whole Bor-Majdanpek copper mining complex stocks, sills, and dikes. Pyrrhotite, chal- is put into operation in 1962, it is expected to copyrite, and pentlandite form low-grade dis- produce annually 55,000 tons of wpper, 3 tons SRIMARY COPPER RESOURCEXS 67 of gold, 34 tons of silver, 400,000 tons of pyrite Skonriotissa Mine, Cyprus Mines Gorp.- concentrate, 230,000 tons of sulfuric acid, The property situated at the foot of h'oucassa 575,000 tons of superphosphate, and 6,000 tons Hill was probably the largest of the ancient of synthetic cryolite. producers. The massive sulfide ore body is flat-lying, lenticular, roughly elliptical in plan, Asia about 2,000 feet long, and as much as 600 feet widetapering from a thickness of a few feet CHINA at the edee to 150 feet near the center. It is There are maycopper occurrences in China. intensely impregnated with sulfates of copper, A Chinese source reports that discoveries of iron, and zinc-including chalcanthite, bro- more than 3,000 copper deposits have been chantite, and melanterite. The ore reserve made mainly in haoning, Hopeh, Shansi, estimate as of December 31, 1960, was 2,750,000 Kansu, Szechwan, Yunnan, Kweichow, and tons. containing- 2 ~ercentcomer - and 40.0 Anhwei hvinces. Intensive prospecting, ex- sulfur. ploration and development are credited for the Msvrovouni Mine, Cy rus Mines Gorp.-The more than tenfold increase in mine production ore body is a large flat-Yying body of cupreous and additions to resources of copper dunng the pyrite. It is almost completely surrounded by past decade. The most significant producing andesitic lava that has been hydrothermally areas are in the southwestern provinces of altered for hundreds of feet on all sides of the Yunnan, Szechwan, and Kweichow. ore. The ore body shows extensive seconda Approlfimately 80 percent of tne copper alteration of chalcopyrite to chalcocite, covg deposits in China are of four tgpe;: Bedded lite, and bornite. There are localized variations deoosit3. stringer-vein disseminated denosits. in copper content from 1 to 10 or 12 percent or 'ohtact mplace;ueats, and co~,l,er-berrril~giyrite.' more in bodies of sizeable tonnage. Crude ore The Tunzsh'uan and I-nien mims in YUI~IIUIIproduction in 1960 totaled 873,000 tons, com- provincelare in bedded deposits; the Chung- pared with 913,000 tons in 1959. The ore t'iao Shan mine in Shansi and the Te-hsing reserve at the end of 1960 was estimated to be mine in Kiaogsi are in stringer-vein dissemi- 2 million tons. averahe- - 3.6 nercent comer.. nated deposits; the ore bodies of the T'ung- and 47.5 percent sulfur. kuan-shan mine in Anhwei and the T'ien-pao- The Cvnms Sul~hurand Comer Co.. Ltd.. shan mine in Kirin are contact-replacemeah; a ~ritis6Acornpan?, produced -ckment copper the Pai-yen mine in Kansu exploits cgriferoy- from leach solutions at the inactive Lirnni mine pyrite bodies; the deposits of the no-yuan from May 1958 until August 1959, when mining mine in Shantung are of the vein type; the operations wereresumed. In 1959 the company Kuang-t'ung mine in Yunnan, the Hui-li mine continued stripping operations at its Kinousa in Szechwan, and the Wei-ning mine in Kwei- opencast mine, mming about 80,000 tons of chow work copper-bearing shale rock; and the ore-averaging 0.88 percent copper. Ore re- deposit at the T'ao-k'o mine in Shantung is the serves at the end of March 1959 were 162,500 copper-nickel type. tons, averaging 0.26 percent copper at the In 1959 the copper ore reserve of China was Kinousa mine and 2,235,000 tons of 1.30 percent estimated between 3 to 5 million tons of copper copper at the Limm mine. (content of ore).

CYPRUS The Mosaboni and adjacent Badia mines of Cyprus was perhaps the earliest im ortant the Indian Copper Corp., Ltd., have been the roducer of copper smelted from s&!e ores. only significant ,producing copper mines , in $he metal was undoubtedly produced and de- India. Exploration and development are bemg livered to the Egyptian kings before the Island conducted by the corporation at the Surda was conquered by Tbotmes I11 about 1500 B.C. mine and Pathagarah prospect northwest of the The Roman occupation of Cyprus in 58 B.C. present working area. The Mosaboni and followed 14 centuries of control by Egyptians, other mines are in tha Singbhnm district of the Phoenicians, Assyrians, Persians, and the Ptole- State of BihHr, 15 miles south of Ghatsila, 135 mi-. Roman production was probably active miles from Calcutta. Ore reserves as of Decem- until A.D. 200. There was oo interest in metal ber 31, 1958, were estimated at 4 million short mining from the Roman period until 1878 when tons, averaging 2.51 percent copper. The Great Britain gained control of Cyprus. Casual principal ore mineral is chalcopyrite, which prospecting was carried on between 1882 and occurs in vains in altered granite. 1914. More intensive exploration was re- Occurrences of copper reported in qaripus sumed in 1919, and cupreous pyrite has been states are in Botang, near Rangpo in Siklam; active1 mined since 1922, except during World Khetri and Daribo in Rajasthan; Baragonda War I[ in the district of Hazaribagh; and Bairukh~in 68 COPPER Santhal Parganas,, both in BihSr; Belli uda in copper mine in Japan. Mining was suspended the Chitaldrug dwtrict of Mysore, hora; in 1946 because all workable ore had been de- and the Tehri-Garhwal districts of Uttar pleted; however, copper is being recovered by Pradesh. Other than the Singbhum belt only leaching and cementation. The reserve is es- the deposits in Sikkim and Rajasthan are said timated at 20 million tons of ore with a grade to be promising. Investigations of the de- of 0.4 percent copper. Annual production is posits at Khetri and Daribo in Rajasthan by about 1,000 tons of copper. the Indian Bureau of Mines and Geological Hanoka Mine, Dowa Mining Co., Ltd.--Thls Survey have been encouraging. is 2.5 miles north of Odate station, Akita-ken, and is known as the largest typical massive ISRAEL kuroko or black ore deposit in Japan. The de- The Timma mine of the Israel Mining posit consists of more than !O irregularly mas- Industries, 15 miles north of the Red Sea ort sive ore bodies distributed in an area 3 miles of Mat, is in the area of the fabled Ani long and 1%miles wide. Ore minerals are wp- Solomon's mines. Operations began in Apr per, lead, zinc, and iron sulfides with some gold 1958 and in 1959, 495,000 tons of ore, contain- and silver. The ore reserve as of September ing 1.45 percent copper, was processed to yield 1958 was 1.85 million tons. containine., 1.2 4,930 tons of copper. Proved reserves are percent copper. estimated at 17 to 18 million tons of ore, averag- The Mitsubishi Metal Mining Co.. Ltd.. OD- ing 1.4 percent copper. New deposits discov- erates 14 mines and produces aFout 20,000'to& ered in April 1960 are expected to double the of 21 percent copper concentrates annually. potential ore reserve. Eleven of these mines have narrow vein de- The Ti& deposit is a sedimentar one with posits, and three work massive, cupriferous cop er mineralization difIused in san Bstone and pyrite deposits. sha? y sandstone rock. The copper occurs Hitachi Mine.-The Nippon MiningCo.,Ltd., mainly in the form of chrysocolla (copper property is in Ibaraki-ken. The deposit con- silicate). Ore is mined b the open pit method sists of about 60 cupriferous pyrite ore bodies and is leached with sul&c acid. - Copper is occurring in an area 2,500 meters long and 1,000 precipitated from the acid copper sulfate solu- meters wide. The company operates 17 otlier t~onwith scrap iron and recovered as cement mines in various sections of Japan, and the ore copper, averagmg about 80 percent copper. reserves of all operating properties in April 1957 were about 40 million tons. JAPAN Ashio Copper Mine.-This famous mine, op- Deposits of copper are widely distributed in erated by the Furukawa Mining Co., Ltd., is Japan. A reserve estimate of 85 million tons about 70 miles north of Tokyo in the Tochigi- of ore, avera g 1.4 percent, was made from ken. The deposit is one of the largest of the a Japanese 8"overnment surveF of 184 mines quartz-vein type in Japan and has been worked in 1956. Most of the ore bodm contain less since 1620. Besides the true fissure veins, ir- than a few hundred thousand tons but they regular deposits of chalcopyrite called kajika commonly occur in clusters. The bedded are found at the intersection of numerous radial cupriferous pyrite-t e deposit is the most pro- veinlets or near the axis of folding in sedimen- ductive in Japan. qhese are massive, pyritic tary rocks. Production amounted to 28,500 replacements of green schist. The sulfide tons in 1959. mmerak present are pyrite, pyrrhotite, chal- and sphalerite. Another type of rep acement is known as blaqk ore; these de- Copper mining replaced the production of posits contain alena, sphalente, chalcopyrite, gold as the leading mineral industry of the and pyrite repf~ngtuffs and shales. Many Philippines in 1959 owing to the expansion of Japanese n+es obtain copper from fissure operations by the four major producers. vems contaming chalcopyrite associated with Toledo Mine.-This open-pit mine of the pyrite or ,pyrrhotite. Some of the larger Atlas Consolidated Mining & Development Japanese nunes are: Corp. in Cebu is the largest in the Far East. Besshi Copper Mine.-This mine of the Sumi- It accounted for 43 percent of the total copper tom0 Metal Mining Co., Ltd., is in Ehime-ken out ut in the Philippines in 1959. Almost 4 in Shikoku. The ore is cupriferous pyrite, milion tons of ore, averagin 0.62 percent averaging 2.16 percent copper in a reserve of copper, was delivered to the milf for processing. about 7 million tons. The known ore bod$ is 1,000 feet wide and 400 Kosaka Mine.-Operated by the Dowa Min- feet deep and is a ssemmated porphm type ing Co., Ltd., this is at Kazunogun, Akita-ken. deposit. Chalcopyrite is the princ~pal ore In 1913 this property was considered the largest mineral. The total reserve at the end of 1959 2.62 prated in the Union of South Africa) directly Mindola ore body ...... 81,106,000' 3.15 or through its subsidiaries M.T.D. (Mangula), Total...... Ltd., and M.T.D. (Sanyati), Ltd. Mangu1a.-The largest copper mine in South- Chibuluma Mimes, Ltd.-The property is in em Rhodesia is in the Lomagundi District, 30 the Nkana South Limb area about 7 miles west miles north of Sinoia and 115 miles northwest of Kitwe and about 34 miles southwest of the of Salisbury. The ore is disseminations of Mufulira mine. Ore reserves at June 30,1960, sulfide minerals, mainly bomite and chalcocite, were: in folded structures of arkoses and shales. Cowr. CWoEI mm rons pnccnt ~rmi Mineralization extends for 3,000 feet with a Chibuluma main ore body-.. 7, 420, 000 5. 03 0. 21 width at the center on the surface of 300 feet. Chibuluma West...... 2,370,000 4.47 .07 Ore reserves in 1960 were 26 million tons, aver- -- aging 1.36 percent copper. Total ...... 9, 790, OW 4.89 0: 18 Other important deposits in this area are the Mine productton for the year ending June 30, replacement ore bodies of the Copper King and 1960, was 575,436 tons of ore, averaging 4.65 Copper Queen mines in the Sebungwe District, percent copper and 0.23 percent cobalt; 76,362 60 miles west of Sinoia; the Alaska mine 12 tons of copper concentrate were treated by miles west-southwest of Sinoia, where copper Mufulira Copper Mines, Ltd., yielding 26,465 minerals occur in a replacement deposit in tons of copper; 36,524 tons of cobalt copper dolomite, and quartzites and ore reserves are concentrate was treated at the Ndola plant, estimated at 5 million tons of 1.87 percent cop- producing 9,778 tons of cobalt matte, contain- per; and the copper-gold carbonate lodes 32 ing 9.46 percent cobalt and 11.61 percent copper. miles west of Sinoia. Another producing prop- The cobalt matte is shipped to Soci6t6 Gbn6rale erty is the Umkondo mine in the Sahi valley, Metallurgique de Hoboken in Belgium for Bikita district, where wpper minerals occur in refuimg. beds of shale and quartzite. Umkondo reserves Mufulira Copper Mines, Ltd.-The company on September 30, 1959, were 360,160 tons of operates the second largest Copperbelt mine ore, containing 3.35 percent copper, sulfide, and and the largest in the Rhodesian Selection oxide. Trust group. The property is 26 miles north- east of Kitwe. There are three parallel mineral- KENYA ized beds at Mufulira, separated by 25 to 45 feet of waste. The two lower beds coalesce The Macalder-Nyanza copper mine, operated toward the northwest to give a thickness of by Macalder-Nyanza Mines, Ltd., south of more than 100 feet in places. Ore reserves on Nyanza near Lake Victoria, produced 1,855 June 30, 1960, were 179 million tons, averaging tons of copper in 1960. It has been estimated 3.35 percent copper. A major expansion of that the known ore body will support this ratZ the producing capacity of Mufuliia was bein of ~roductionfor approximately 12 years. developed at Mufuliia West and was designe2 to increase capacity by 50 percent. MAURITANIA Roan Antelope Copper Pines, Ltd.-The de osit is in the southwest corner of the Copper- The principal copper deposit in Mauritania, be Pt near the town of Luanshya. The deposit known as the Guelb Moghrein mine, is about is large and is important for the great length of 2.5 miles from Akjoujt. About 9 million tons ore developed around the nose and along the of oxidized ore, averaging 2.3 percent copper, is limbs of the fold in an ore bed 25 to 30 feet in the upper part of the ore body,.and almost thick. Ore reserves at June 30, 1960, totaled 17 million tons of cupriferous pyrite with 1.5 94.6 million tons of 3.04 percent copper. Mine percent copper is in the lower part. The deposit output for the year ending June 30, 1960, was is being developed by SociBt6 des Mines de 6.66 million tons of ore, averaging 1.85 percent, Cuiae de Mauritanie (MICUMA). Lack of and production of copper was 103,422 short water and mineral composition present prob- tons lems in concentration of the ore. 72 COPPER SOUTH-WEST AFRICA Narrap, Wheal Julia, Nababiep West, and the Carolusberg. The ore bodies occur in meta- The Tsumeb mine of the Tsumeb Corp., morphic roch that consist chiefly of paragneiss, Ltd., is the major source of copper. Copper granulite, quartzite, and schist. Mixtures of minerals-including tennantite, enargite, chal- the oxide minerals, brochmtite, chrysocolla, cocite, and bormte.-are associated m sub- and malachite show in some of the outcrops. stantial amounts mth lead and zmc ores m Below the oxidized zone, usually less than 70 massive replacement lenses in dolomite. Ore feet, are bornite, chalcopyrite, and chalcocite. reserves above the 3,150-foot level on June 30, These minerals occur in fine17 disseminated 1959, totaled 8,165,000 tons-averaging 5.29 form, in coarser aggregates with interconnecting plercent copper, 14.36 percent lead, 4.45 ercent veinlets, and in massive form. Sulfide ore zmc, and 0.013 percent germanium. 6rilling reserves on June 30, 1959, totaled 27.8 million below the 3,150-foot level has indicated a tons, averaging 2.19 percent copper. minimum of 2 million additional tons of ore- Artonvilla, Campbell, Harper, and Messina.- averaging 4.6 percent copper, 7.1 percent lead, In Transvaal, these four producing mines, oper- and 1.9 percent zinc. Exploratory drhg on ated by Messina (Transvaal) Development Co., the Tsumeb Asis claim near Komhat has dis- Ltd., are near the town of Messina, 6 miles closed two ore bodies of about 1 million tons south of the Limpopo river which forms the each, averaging 11 percent combined copper boundary between the Union of South Africa and lead; production started in April 1962. and Southern Rhodesia. The ore bodies are The Tsumeb Corp., Ltd., was erecting a veins and breccia pipes lying in a zone striking copper smelter at Tsumeb which was completed northeast for about 10 miles along the Messina and began production of blister copper in fault. The principal ore minerals are chal- November 1962. copyrite, bornite, and chalcocite. Ore reserves on September 30, 1961, totaled 6,003,810 tons, UGANDA containing 1.57 percent co per The Campbell The Kilembe mine, operated by Kilembe mine presently accounts Lr about half of the Mines, Ltd., is in the foothills of Mount ore produced.~ Ruwenzori in the Toro district of Western Palabora Mining Co., it&-Controlled by Uganda. Two ore bodies are being worked. the Rio Tinto Co., Ltd., of London and the Both deposits are irre arly shaped and occur Newmont Mining Corp. of New York, this over a strike length oP about 7,000 feet and an company is developing a long known copper average thickness of 40 feet. The upper part deposit at Loolekop, Palabora, northeast Trans- of the East deposit is near the surface and is vaal about 75 miles east of Pietersburg. Drill- mined b the open-pit method; the lower section ing confirms the existence of a low-grade ore of the I3"ast deposit and the North de osit are body suitable for open-pit mimng. Ore reserves mined by underground methods. $he ore have been estimated at 5.7 million tons of 1.26 contains a wide variety of minerals which percent copper and 24.9 million tons of 0.51 occur as disseminations, stringers, seams, and percent copper per hundred feet of depth. small blebs within the granulitic host rock. Production of 2,265 tons of wpper in concen- Ore minerals are cuprite, malachite, chrys- trates was reported in 1961 for the first t,ime. ocolla, and chalcocite in the upper zone and chalcopyrite, pyrite, pyrrhotite, and linnaeite in Australia the lower. Ore reserves estimated at the end of 1958 were 8.2 dion tons, containing 2.31 During the 1950's Australia became one of percent copper and 0:18 percent cobalt, and the major world sources of wpper. Mine 1.57 million tons, contaming 1.23 percent wpper production of 1950 had increased eightfold to ahd 0.22 percent cobalt. Blister-copper pro- 122,000 tons by 1960, mainly because of con- duction was 17,200 tons in 1962. tinuing expansion at the Mt. Isa mine. Pour mines produce approximately 90 percent of REPUBLIC OF SOUTH AFRICA Australian copper. The balance is obtained Most of the copper production of bhe Republic from small copper mines and byprqduct re- of South Africa comes from two widely sep- coveries at the large silver-lead-zinc mlnes. arated deposits, the O'okei properties near Mt. Isa Mine.-This property of the Mt. Isa Springhok in ~amaqualanf(Cape of Good Mines, Ltd.-in which the American Smelting Hope Province) and the Messina mine in the and.Refining Co. of the United States has a Northern Transvaal near the Southern Rho- cantm1hg interest-is the largest producer, desian border. accodnting f6r 60 ercdnt of the 1961 output The principal mines operated h the O'okeip from Australia. &e deposits are s~tuatedat Copper Co. are the Nababiep, Jast O'okeip, Mount I&, 600 miles west of Townsville, in PRIMARY COPPER RESOURCES 73 Queensland. The host rock tor the ore bodies belt extending from the northern side of Mount is known broadly as a silica-dolomite rock, Lye11 to the northern side of Mount Owen on which consists of brecciated dolomitic and the south, a distance of 2% miles. The ore pyritic shales with massive and, at times,, deposits are associated with the schist-conglom- structureless siliceous and dolomitic rocks. erate contact. Massive sulfide ore bodies occur The chief ore mineral is chalcopyrite, occurring on or near the contact and low-grade dis- as fracture and vein filling in the silica-dolomite seminated ore bodies away from the contact. bodies. Oxidized and secondarily enriched The ore consists mainIy of chalcopyrite with copper ores occur in the oxidized zone near the some bornite. Ore reserves on June 30, 1962, surface. The estimated reserves of copper ore were 23.5 million tons, averaging 0.80 percent on June 30, 1961, were 24.5 million tons, copper. Mine production of copper in fiscal averaging 3.7 percent copper. 1962 was 12,332 tons. Bfount Bforgsn Mine.--Operated by Mount Peko Mine.-This mperty of Peko Mines Morgan, Ltd., it is also in the State of Queens- N.L. at Tennant creeR is the only co per mine land, 23 miles southwest of Rockhampton, on in Northern Territory. The ore bo ay or lode the Dee River. The ore .body, including the contained some copper in the oxidized zone; Sugarloaf section, is an irregnlar quartz-pyrite high-grade copper ore, containing native copper, mass, having a maximum length of 2,100 feet cuprite, and malachite was found near the and a maximum width of 900 feet. The water table. Primary ore-containing 4 to 11 p~incipalore mineral is chalcopyrite. Produc- percent (average 8.5 percent) copper and 0.05 t~onin 1961 was 9,300 short tons of copper and to 1.25 ounce gold per ton--occurred at 350 54,000 ounces of gold in concentrates. Reserves feet and continued in depth. The co er as of June 30, 1961, amounted to 13.8 million occurs chiefly as chalcop te, while the goy%is tons of ore, containing 0.116 ounce gold per ton fine grained and is closeY' y associated with the and 1.10 percent copper. chalcopyrite. Ore reserves in mid-1959 were ldount Lyell-This group of mines is about estimated at 1 million tons with an average of 18 miles from Macquarie Harbour on the west 6.3 percent copper. Pmduction of copper in coast of Tasmania. The mines are in a narrow 1959 was 7,500 tons in concentrates. Foreword The Materials Survey series being prep* b the Bureau of Mines, Department of the Interior, under the sponsorshp o9 the Office of Emergency Planning, is designed to present in separate documents a wmpilabon of wm- prehensive fundamental mformation for those metals and mmerals easentlal to National Security. These Surveys summarize the demand-supply position in the United States and include mformation on production, consum tion, imports, e orb, capacities, substitutes, and pertinent history, usuaH y m. some detai1"Back to 1925. The properties and uses of the commodity and its and compounds are described. Exploration, mining, metal- ~$fa~tt"~riCationmethods are diwssd. Domestic and foreign primary an secondary resources and reserves are covered. An extended presentahon of the structure of the industry, employment and productivity, research and development legdation, taxes, and Government wartime controls is included. Other specid data are presented for particular commodities. This Copper Materials Survey was prepared in the Division of Minerals under the direct su ervision of Paul F. Yopes, Chief, Branch of Nonferrous Metals, and ~onahf~.Irving, Assistant to the Chief, Division of Minerals. The manuscri t was reviewed, in whole or in part, by s ecialists in the Bureau of Mines, ~eojogicalSurvey, and various segments of t!e copper industry. CHARLESW. MERRILL, Chief, Divkim of Minerals. v COPPER BIBLIOGWHY

The Anaconda Company. This is Anaconda. New Northern Rhodesia-Chamber of Mines. Yearbook. York, 1960, 59 pp. Rhodesian Printers Ltd.. Salisbury,.. Southern Rhode- Bureau of Mimes. Copper. MS 6, 1952, 556 pp. sia, 1959, 93 pp. Butler, B. S., and S. W. Burhanks. The Co per Parsons, A. B. The Porphyry Coppers. AIME, New Deposits of Michigan. US. Geol. Survey 8rof. York, 1933, 581 pg., . Paper 144, 1929, p. 101. Peets, Robert G., mng History at Cornwall, Pa. Butts, Allison. Copper, The Metal, Its AUoys and Min. Eng., v. 9, No. 7, July 1957, pp. 741-744. Compounds. Reinhold Pub. Corp., New York, 1954, Pelletier, J. D. Geology of the Sun Manuel Mine. p . 21-82. Eng. and Min. J., u. 9, No. 7, July 1957, pp. 76&762. c&wa H. M. Lead, A Materials Survey. ~u~inesPeterson, Neb P., and Roger W. Swanson. Geology of Inf. &c. 8083, 1962, 194 pp. the Christmas Copper Mine, Gila County, Ariz., Ch. Edwards, A. B. Geology of Australian Ore Deposits. in Contributions to Economic Geology, 1956. US. 5th Empire Min. and Met. Congr., Australia and Geol. Survey Bull. 1027(h), 1956, 351-373. New Zealand, v. 1, 1953, 1290 pp. Po off, C. C. Block Caving at %lly Mine, The Gardner, E. D., C. H. Johnson, and B. S. Butler. Ihaconda Company, Butte, Mont. BuMimes Inf. Copper Mining in North America. BuMines Bull. Circ. 7758, 1956, 102 DP. 405, 1938, 300 pp. Schmidt, ~arrisonA. -The Cop er Province of the Geolo 'cal Survey of Finland. The Mines and Quarries Southwest. Min. Eug., v. 11, 80.6, June 1959, pp. of #hand. 1954, 123 pp. 597-600. Grant, M. North. The Copper Industry in Yugoslavia. iiixtwnth Internatiunal Gmlogicsl Congress. Copper Co er Division BDSA, US. Dept. of Commerce, v. Resources of the World. V. I and 2, George Banta 5 E.2, Autumn 1958, p#. 10-!1: Hardwick, W. R. Open- ~t M~nmg Methods and Pub. Co.. hlenasha. Wis.. 1935. 855 DD. Practices at the Chino Mines Division, Kennecott Skinner, ~LterE. ~ining'~earbooki961. Walter E. Copper Corp., Grant County, N. Mex. BuMines Inf. Skinner and Financial Times, London, 1961, 791 pp. Circ. 7837, 1958, 64 p Smith, M. Clair. Methods and Operations at the Killin, A. F. Survey of 'he Copper Industry in Canada. Yerington Copper Mine and Plant of the Anaconda Miner. Inf. Bull. MR47, Mtner. Res. Division, Dept. Co., Weed Heights, Nev. BuMies Inf. Circ. 7848, - - OD. Mines and Tech. Surveys, Ottawa, Canada, 1961,107 1958., 37 A. PP. Spence, W. I. The Mesaina Copper Mine. Paper for Lasky, S. G. Geology and Ore Deposits of the Lords- 7th Commonwealth Min. and Met. Cong., Union of burg Mining District, Hidalgo County, N. Mex. US. South Africa, April 1961. pp. 1-19. Geol. Survey Bull. 885, 1938, 62 pp. McWilliam, John R. Mining Methods and Costs at Thurmond, Robert E.. and Walter E. Neiwicks, Jr. The Anaconda Company Berkeley Pit, Butte, Mont. Geoph s~cal Discovery and Develo ment of the BuMines Inf. Cue. 7888, 1959, 46 p Pima Kine, Pima County, Aria. APME Transac- Mining Journal (London). Russian &pper Reserves. tions. Min. Enn..-. Februarv 1954. DD. 197-202. V. 255, No. 6541, Dec. 30, 1980, . 786. Tuck, Frank J. Stories of Arizona Copper Mines. Mukiet, T., A. Bem, and T. &Idowski. Mining Arie. Dept. Min. Reg., Phoenix, Ariz., 1957, 120 pp. Activities in Poland. Min. and Quarry Eng., v. 25, White. Walter S.. and James C. Wright. The Wbiite No. 4, April 1959, pp. 166-168. Pin; Copper Depmit, Ontonagan County, Mich. Nahai, Lotfollah. The Mineral Industry of Turkey. Econ. Geol., v. 49, No. 7, November 1954, pp. BuMines Inf. Circ. 7855, 1958, 140 pp. 676-716. CHAPTER 4.-SECONDARY COPPER RESOURCES

A lar e reserve of secondary copper has been The new scrap generated in fabricating and accumJated and is continually being aug- manufacturing semihished and fin~shedprod- mented because of its indestructibility and the ucts from primary copper and copper-base-alloy consumption pattern of the metal and its alloys. forms does not form a reservoir supply to Every use of new co,pper in any form becomes a supplement product~on of primary copper. potentlal part of thls resource except those few Examples of new scrap are defectlve castmgs, applications where recldmation is impossible, clippings, punchings, turnings, borings, skim- for example, copper in chemical compounds mn~,drosses, and slag. Such scrap represents used as fungicides and copper sqd brass powders a crculating quantity of cppper prenously employed m making pamt pigments. Each accounted for as sup ly of pnmary copper and year this reservoir prondes ap roximatel one returned to the fagmating process without fourth of the copper consumei in the dited reaching the ~roductstage. However, data States in unalloyed and alloyed products. The on the %oreme'nt of new &up have significancr collection and processing ofcopprr and copper- us indicators of business activity ln fabncatmg- basealloy scrap mtosecondary metal constitutes and scrap reclamation industries. an important sepent of thf impper industry in all malor consunung countaes. SOURCES NATURE Collection of scrap is camed on in almost Copper recovered from wpper scrap, wpper- every community. In many there are collec- alloy scrap, and other copper-bearmg scrap tors or dealers that sort, bale, and otherwise materials as wpper metal, or as copper content prepare the salvaged scrap for shipment and of alloys, chem~cals,or com ounds is known as sale to primary smelters, secondary smelters, secondary copper. As de& ed, the term in- eludes the co per content of copper-base and ingot makers, brass mills, chemical plants, or other copper-gearing alloys recovered in alloy other fabricators. However, the principal form, as well as refined copper produced in sources of copper and copper-alloy scrap are the proce+g various kinds of scrap. Some brass heavily populated industrial centers; most of scrap 1s smelted for separate recovery of its the plants engaged in recovering secondary copper content; however, a large percenta e of copper are located in these areas. Distribution reclamed brass scrap a remelted into f rass of the primary and secondary smelters and ingots that are sold aa brass in the secondary brass mills (1958) producing most of the market. Inasmuch as the copper content of secondary copper in the United States is as such brass substitutes.for primary copper in industrial and commercial products of consump- follows: tion, it contributes to the available supply of State: Primaty and secondary smelters: No. Ojpladl copper and may validly be covered by the term IUmom ...... 15 "secondary copper." The same reasoning is Ohio ...... 12 applicable to other wpper alloys and chemicals. New York ...... 12 New Jersey...... 10 California...... 9 KIMls OF SCRAP Massachusetts...... 5 Michigan...... 5 Secondary copper is recovered from two Brass mills: Connecticut...... 15 rincipal classes of scrap, these are old and new. Illinois ...... 6 %owever, pnly old scrap is available from the Michigan ...... 6 accumulat~ng reserve of secondary copper Pennsylvania ...... 6 through reclamation of copper, brass, bronze, New Jersey ...... 5 New York ...... 5 and other alloy products that have been used ...... and then discarded because they are obsolete, California 3 worn out, or damaged. Such articles are wire, Types and quantities of old scrap consumed fired,cartridge cases, pipe, automobile rad~ators, by producers of secondary copper, 1956-60, bearmgs, valves, screening, lithographic plates, are shown in table 9. etc. COPPER TABLE9.-Cmsumption of old scrap, short tons - 1958 - Numioun 1,142 Auto radbtors (unsmted)...... I 51 681 B~IC...... 23: 9a6 Cartridge owand brass ...... IS. se4 commslaon or red b- ...... 65.137 Iaa hraw-~~~~~~~ I 1 575 127:537 2, 838 110 321 1n:m 58,674 -63,238 Total ...... 541,021 -

MAGNITUDE OF INDUSTRY throu h 1960, more than 16 million tons of secon2 ary copper was recovered from,old scrap. Near the beginning of the 20th century, the An important aspect of tnese data is that an secondar metal industry comprised a group of ever increasing resource is being created that independkt junk collectors and dealers who is capable o* providing about one-third of the gathered, sorted, and sold scrap met& and national requirements. waste matenals to relatively uncertain markets. There is no statisiical series showing the As more scrap metal sources were ,developed amounts of copper consumed in end-use items and collection became better orgamzed, some that would indicate the quantity in service in of the collectors and dealers sought to increase nondissipative uses; nor is there any related their margin of profit by remelting their scrap quantitative data about consumption and recla- and producing commercial ingots. These in- mation by an mdustry classification. Although gots were generally poor in grade, by present it is generally known that more old scrap is standards. Having no precedent with which salvaged from capital goods such as buildings, to base ex ansion and improvements, this em- ships, railroads, bridges, and industrial ma- bryonic iniustry added technical personnel and chinery than from consumer goods such as began educating itself in the art and technology automobiles, radios, and cooking utensils, there of reclaiming values from swap and waste ma- are no continuing statistics showing significant terials. The quality of products and the degree uses of copper in units of capital goods that of specialization in all se ents of the industry would support the construction of an estimated soon improved consideraTy. Collecting, mar- reserve of copper in use. keting, melting, refining, and alloying became However, table 10 presents an interesting individual operations, each contributing to the development showing expansion ot the cop er general advance of the industry as a whole. in-use pool in the United States from 3 &on As a result, the secondary copper industry tons at the end of 1907 to almost 33 million has grown to be the largest of the nonferrous tons at the end of 1960. These figures are secondary metal industries. Approximately 25 based on the estimate that three-fourths of the percent of the total copper consumed in the new cop er is consumed in the manufacture of United States is produced from old scrap. The reclaima! le products. industry consists of several thousand collectors Although adequate data for adjustment of and dealers, several hundred foundries, about the annual increments are not available, there eighty in ot makers and secondary smelters, are some factors that should be wnsidered in the around fif ty brass mills, and a dozen primary accumulation of the in-use ool Examples of smelters which process some scrap. These proc- such factors are imports anJ'. exports of copper- essors also recover an equivalent amount of bearing manufactured products and imports copper from new scrap and the total from new and exports of new and old copper scrap that and old scrap often approaches recoverable are not included in calculating apparent con- mine production. sumption. However, the error introduced by exclusion of this foreign-trade material is believed to be consistent with the limits of ACCUMULATING POOL accuracy in other portions of the problem. Consumption of new cop er in the United States from the beginning oi' recorded produc- WORLD RESERVE tion in 1845 through 1960 totals approximately The major uses of copper in the principal 51 million tons. In the period from 1908 foreign consuming wuntnes are about tne same SECONDARY COPPER RESOURCES 77 TABLE10.-Estimated amumulatwn of copper-in-usein the United Sfafes, 1846-1960 (thousands of tom)

I Consumption. apparent Pool of copper-in-use Year ncrease=75 1 New Old Total percent of Total rtt copper scrap total minus :nd of year old scrap

18451907...... 16, 083 In use through 1907...... 1908...... 240.0 1909...... 344 3 1910...... 366.2 1911...... 340.9 1912...... 388. 0 1913...... 406. 1 1914...... 350. 8 1915...... 568. 3 1916...... 739.4 1917...... 697. 4 1918...... 830. 8 1919...... 457.2 1920...... 526.9 1921...... 305.5 1922...... 448.3 1923...... 650.2 19% ...... 677.4 1925...... 700. 5 1926...... 785. 1 1927...... 711.5 1928...... 804 3 1929...... 889.3 1930...... 632.5 1931...... 451.0 1932...... 250.6 1933...... 339.4 1934...... 322.6 1935...... 441. 4 1936...... 656. 2 1937...... 694. 9 1938...... 407. 0 1939...... 714. 9 1940...... 1,008.8 1941...... 1,641.6 1942...... 1,608.0 1943...... 1,502.0 1944...... 1, 504.0 1945...... 1,415.0 94...... 1,391.0 1947...... 1, 286.0 1948...... 1,214.0 194...... 1,072.0 1950...... 1,447.0 1951...... 1,304.0 1952...... 1.360. 0 1953...... 1,435.0 1954...... 1,235.0 1955...... 1,336.0 1956...... 1,367.0 1957 ...... 1,239.0 1958...... 1, 157. 0 1959...... 1, 183. 0 1960...... 1,148.0 Total...... 51, 084 3 16. 481. 7 29. 630. 0

- Source: Merr Manee of the !era1 Industries n the Emnomj .lThe Miners1 I utrles. AIME. iea Y0.k. 10J( 78 COPPER 32,630,000X 113,562,000 as those in the United States with a similar World secondary resource= relationship existing between consumption of 45,001,300 scrap and total copper. Further, scrap 1s World secondary resource= 82,000,000 tons. collected, marketed, and processed in foreign World consumption of 113,562,000 for the countries in much the same manner as it is in period 1908-60 was compiled from various the United States. This is particularly true sources. Smelter production IS used for the in Europe where 40 to 45 percent of the World periods 1908-21 and 1939-45, as there are no copper is consumed, pripcipally in Great World consumption data for those years; Britain, West Germany, U.S.S.R., France, and consumption data appearing in the American Italy. Because of this implied parallelism, Bureau of Metal Statistics 1933 yearbook are the accumulated copper that is recoverable used for 1922-25; Bureau of Mines data are but still in use in the Wodd is estimated by used for the other years. Although the con- applying the ratio of World to United States sumption statistics used in developing an es- wnsumption for the period 1908-60 to the timate of the World secondary copper reserve resource pool as developed for the United States. are not strictly comparable, the Merences are World sewndary resource, World consumption, not great, and the result indicates the probable U.S. aecondsry resource ' U.S. consumption magnitude of such a resource. SECONDARY COPPER RESOURCES BIBLIOGRAPHY

Barbour. Perov E. Wondarv Cou~er. Min. and bv Allison Butts. Reinhold Pub. Coru.. New York. Met. hc. of America, New Pork, iG36, 85 pp. Bureau of Mines. Mineral Resouroes. Copper Chap ters, 1910-31. Bureau of Mines. Minerals Yearbook. Copper Chap tern, 193260. Cochran, Ray. Secondary Copper and Co per Alloys. Ch. in Copper, The Metal, Its Alloys and &ompounds, -Copper,' BuMine CHAPTER 5.-TECHNOLOGY

Technolo is defined as the science of magnetic and electromagnetic methods on a s tematic %owledge of the industrial arts. fai& close s acing. Soliie reconnaissance geo- $e e ansion of near1 all phases of industry chemical wort may also be carried out. Results is due"P argely to deve7 opment of the science obtained are used to determine the extent of through research and application of scientific sta e three, detailed ground surveys. This knowledge through engineering. Man incf udea chechg of geophysical .anomalies must continually seek improved using corresponding ground techniques, de- increase efficiency of operations tailed geochemical work and geolo@cal mapping costs. and possibly shallow drilling, ittin stn and trenching. The extent ofthe ahal mi PROSPECTING AND EXPLORATION, program is in turn conditioned by the quality of these results. CURRENT ORE SEARCH TECmQUES The favored exploration approach by some companies is the acquisition of prospects ,by F'rospecting is the search for ore occurrence, option. It also fits into the basic explorataon and exploration is the work involved in gainin oromams of others. knowledge of the size, shape, position, an2 .~~ener&~- the planning and organization of a value of an ore body. These two activities, larre-scale emloration moeram- - consists of four although quite diiereqt in purpose, use the mGn stages: ' same tools. Many mters consider prospect. 1. obtaining an overall picture of the geo!ogy by ing as a phase of exploration and refer to the aerial photography, photogeological interpretation, and search for ore as exploration for new ore field reconnaissance; preparation of a isrge-scale geo- logical map; and development of the geological history bodies; others use the terms interchangeably; of-the area. such as, geochemical exploration and geo- 2. Airborne geophysical exploration, geochemical chemical prospecting or geophysical exploration survey of silta and soils along streambeds and other and geophysical prospecting. The separation prominent expures, and field investigations for map ping widely spaced traverses to locate all superlicial of prospectmg from explorataon is difficult, and mineralization that can be found easily. consequently, prospectmg and exploration of 3. Geological mapping and geophysical, geochemical, copper deposlts are treated as a unit in this and mineralogical prospecting of promising areas on a re ort 4. Ed..ovrng the deposit-ementially, delineatin and %is&rically, minerd de osits have been sampling the ore. More detailed mapping andg geo- discovered by prospectors, focal groups orga- physical and geochemical studies may be neceasary. nized to rospect aqd explore a single property, but the fieldwork wnaists mostly of obtaining samples and smaE companies. The most advanced from the ore body exposed by pitting, trenching, drill- techniques now used-omprising the expensive ing, and shaft sinking. requirements of mapping, driiing, underground Geophysical prospecting is used to measure workings, sampling and assaying, metallurgical and interpret anomalous physical or physico- testing, and other related activities-are be- chemical phenomena within the crust of the yond the financial capacity of individuals or earth. For example, magnetic material m the small companies. The major companies, for earth increases the strength of the norm$ the most part, find operation of small minea magnetic field, and the resulting magnetic uneconomic and generally do not, become anomaly can be measured with sensitive interested in a mining property or a rmneralized magnetometers. Hence this method has been area unless it promis& td bewme a large-scale important in locatin magnetic iron o~es producer. (magnetite) and has feen helpful in tracing Two fundamental a~~roachesto exdoration geological formations and certain types of are common, basic e&doration and broperti nonferrous mineral deposits hamg a greater or acauisition, as well as combinations of the two smaller content of magnetic minerals than the in barying' ~pprtions. enclosing or ad'scent rocks. Various other Bas+ exp oration as practiced by large ex- geophysical met bods, such as resistivity and lorat~oncompanies consists of several stages. radio frequency, de end on electrical kt,an area is selected by a study of the nomena. The petrofmn industry has regional geology, using photogeology as ,a tool. e*ntly successful in developing and a plying Next, the area often is mapped by mborne gravitational and seismc methods to Pocation . 81 82 COPPER of underlying oil-bearing structures. Gravita- in the bottom of the hole during drilling, and tional methods are based on gravity differences the cuttings are brought to the surface with a between different types of rocks, and seismic bailer at regular measured intervals for exami- methods depend upon differences in the speed nation and analysis. of refracted and transmitted seismic waves Diamond his.-These are used widely in through different rock layers. exploration because of their speed, adaptability Data obtained by exploration are required for directional drilling, and portability, and for determining ore reserves, planning mining because they provide accurate information methods and equipment, projecting the scale of about the rock t s drilled. The diamond operations, and other technological and eco- drill is a rotary drEesigned to cut an annular nomic factors essential to establishment of a groove about a central core of the rock pene- mining enterprise. trated. The hit is typically a hollow metal These objectives postulate that the ore cylinder set with industrial diamonds on its body be penetrated by boreholes and/or under- inner, outer, and downward surfaces; it is ground workings at appropriately spaced in- joined to hollow steel connecting rods that are tervals and that the exploratory work be rotated by mechanical equi ment at the collar carried far enough to permit sound planning of the hole. Water GircLting through the of subsequent operations. For exam le, por- hollow rods cools the bit and flushes the he phyry-copper deposits usually are expf ored by cuttings from the hole. The core formed as a network of boreholes or nndergonnd work- the drill advances is recovered in sections for ings on a 100-to-200-foot spacing over the inspection and testing. entire area of the deposit, in advance of mining, Rotary Drills.-These rotate alloy steel or to predetermine the factors that predicate a tungsten carbide drill (tricone) bits in the heavy expenditure for equipment and to avoid bottom of the hole to achieve a constant lacing surface structures on ground that may chip ing, scaling, and grinding action. Down- fater be mined or caved. However, e loration warfpressure of the drill bit is supplied by the of a vein deposit, especially if it is to?e ,ned weight of the string of metal rods that connects by supported stopes, need only be carried far the bit to the rotary table at the collar of the enough to demonstrate the existence of a hole. Cuttings are either bailed or conveyed workable ore body of sufficient extent and to the surface by a circulating fluid such as value to justif relatively moderate expendi- water, air, or a heavy medium mixture (fig. 3). tures for deveI' opment and equipment. De- Hammer Drills.-Their best application is in ferred interest charges on adyance exploration explorator drilliugunderground, where relative- and the cost of maintaining underground ly short hoP es are to be drilled, and core recover workings limit the amount of exploration that is not required. The maximum depth of drii may he done in advance of mimng; hence, in holes for hammer drills is about 250 feet, but many underground mines the developed ore the most efficient range is less than 150 feet. reserve rarely exceeds 10 years and often is These are common heavy rock drills, usin less than 3. A contin+g program of explora- sectionalized, hollow drill steel and staudarf tion and development IS relied upon to add hits. reserves to replace mined-out ore. Boring Underground Exploration Boring is employed extensively, either as the Most prospects and small mines re1 princi principal exploratory method or to supplen~ent pally upon underground methods of exproration: exploration h underground and surface work- A typical example in exploration of narrow ings. SeveraP types of drills are used for this veins is sinking a shaft in or alongside the purpose, the principal ones being churn drills, vein and then driving underground-horizontal diamond drills, rotary drills, and hammer drills. workings known as driits or levels in the vein Churn Drills.-These are employed when at convenient intervals. Exploration for par- solid cores are not required, strati aphic allel ore bodies or to find faulted segments of thicknesses do not have to be measure i=accu- the main ore body is done by diamond drilling rately, and only vertical holes are desired. In or by making horizontal openings (crosscuts) churn drilling, a string of tools with a cutting bit at the lower end is suspended from a rope or that penetrate the enclosing country rock at an cahle and is alternately raised and dropped by angle to the reva ailing strike of the vein or a machine near the collar of the hole. The stratified country rock. In suitable topo- release of tension in the cahle as the bit strikes graphic situations, a horizontal opening or adit the bottom of the hole imparts a slight rotation may be driven into a hillside to reach or follow or churning action to the hit. Water is used a vein that crops out at a higher level. 'Tiw t,1.1.111 6hiw?dPWhpmwit ** is ~WkpI~rpd tri afcFigm,gt,* t Iji"~)f~c~'at,tism-. iaivid vet1 ir.; em- parirjg zt, rr;iw fw cm@xz~~L("L~$BI~, Irk w~&Y- grgbuid mirm 5 twt* ripem tiam- iwIl~dh\ priwi- plsilga p.rcpr~it,ifittid' g~pwiilig-tgi ~tridillto ~iii~ taw hotly alwti try ~IHJ~~F,WB.BB~'.~B"B~~*~, td~ilty) TH~-?C%,~r~d "aft~ift-., la, ra~c~-.tiriiriw, hiif; wqArirtitiii:i j~rid(i&*~t*lirj~- ma>rit rvm~i~iwt:tfia~r amb ~~Xtrzwtljia:hzr3 Ewprari, ssl't~~rscatrly t $1 t!erb w~m,~i~rr~sgf tuiialljg. ,19- Iliaruph ~~plc%ggrttfitill ti1191 CIC~~Ilbl~tzlmt wr~rk ztii"ta 4iiiiliii., iiirz g*iiiyiiriris i- plat4 iiii wrk iiiidiigz r ' I hraw tnw t wrl j,~.i~.lc*ip"".s ypm of cwppr 'crrcp ifr BY~"~B~EIt ia~~j: wj~~v-s*?i.il it3 (lip ali~~~1g~jiflt~gg~ i~prr:aiirrr:-- ti F'P i~iii:tiIyjj~'ky~til'zi t ii~~t fs~ ~~mxsi'hi;_r adi*p&$. t l;as.;ab Ikr2rt;. r ha' salrf~rvi. in rid t Iiiolc. ai%tvlg Iwfttw SBZ~WT, !st%rs tll'@ frp3rti tIw ~lii~H', $1;~ Yr*irns tzrtei ot dt~pmif~ ry 1 LP fm+r uptwtici!f-. iF3 dPi &phg M3 qwrk- of ~;~f$ar\~tre.ar iri*q.wlar for^^ :i1"(-1l"-1~1:dlydwp pit minr aiw ntl-iltlhgl i;.c:rirta.,d d hwri , t r.trc*tiuriof cmtrd proper ~rtpport tct prt*vr*rit 84 COPPER loss of adjacent or overlying ore bodies and which must be done before ore can be produced destruction of surface structures. The large at planned capacity. The average amount of disseminated deposits are mined by open

TABLE11.-Copper ores and copper produeed in the United States, dislributed by principal mining methods

Copper, ore. copper, I Ore. I copper. om. comer. percent I percent I percent mrant I m-t wrwt percent -- 1810 ...... 43 1813 ...... 31 IWB 24 1M7...... 18 1% 8 ...... M 1948 ...... -...-.-.-----.-.------18 1850...... 17 I,, I,, ...... 17 IN2...... 17 1- 18 IBM 10 1955 13 1858 I4 1967 14 1858 I4 1959 I4 1880...... 15 1m...... 15 1mz...... 14 14 1889...... 146,4UI - an unbroken bank. Secondary drilling is vertical holes. When extremely dense boulders required for breakin boulders too large for are encountered, a "drop ball" is used. %re shovels to handle orbf astin unbroken points of adaptable, this is an efficient tool for brealung rock that project above tte digging grade in oversize boulders. In mines where only a few the shovel pit. boulders occur, mudcap or adobe shots, wh~ch Benches of open-pit copper mines normally require no drilling, are used. are from 25 to 60 feet high. The height is Blasting is of primary importance. Good selected to give maximum digging efficiency breakage depends on the proper selection pf but sometimes is limited for ore-waste separa- losives and the proper arrangement of dnll tion. The height may be reduced where the 8es. Gelatinized nitroglycerine explosives are rock is hard and difficult to break and increased used in wet holes and the ammonium nitrate where it is softer. type in dry holes. Usually the charges are Blastholes range in diameter from 6 to 12 placed at the bottom of the hole and exploded inches and are drilled from 2 to tsfeet below by detonating fuse, but often small additional grade. The holes usually are ddled with a charges, ,wmmonly called deck charges, are rotary drill, using multicone-type cutting bits. placed h~ghin the hole. Delays are used Smaller diameter holes s aced more closely are where toe holes or multiple rows of holes are used in harder grounl Distances between tired in the same blast. holes range from 12 feet for 6-inch holes in very Commercial ammonium nitrate, sensitized by hard ground to as much as 50 feet for 12-inch addition of diesel fuel or some other sutsble holes in easily broken ground. In very hard petroleum product, has been adopted as a ground, percussion-type drills with tungsten low-cost efficient blasting agent and 1s used carbide bits are used. PerformancF of heavy widely. The ready supply of the chemicals and percussion-type drills ranges from about 60 to the ease with which they can be formed mto an 150 feet per shift; that of rotary-type drills is efficient blasting agent in the field enables the from about 150 to 500 feet per shift. Bit blaster to repare the explosive on the lob. performance varies greatly, depending on the Ore aniwaste are loaded by full-revolving type of rock; for 12-inch bits it ranges from electric and diesel powered shovels. At most 600 to 3,000 feet per bit. Figures 6 and 7 mines shovels with 4-to-6-cubic-yard capacities show plan and section of primary blasthole are used, but larger mines have shown an arrangements. increasing tendency to use 7-to-13-cub~c-yard For secouda drilling, portable compressors shovels. Four-to-six-cubic-yard shovels gen- and wagon dxs have been replaced at most erally load 3,000 to 6,000 tons per operating mines b self~ontainedunits with compressor shift, and the larger shoveh load as much as and drdinstalled as integral parts. The drills 15,000 tons per operating shift. The larger are mounted on hydraulically controlled arms shovels are particularly useful in waste areas that can be adjusted to drill horizontal or where large boulders can be loaded and dumped 733-7443 0-6'7 FIGURE4.-Utah Capper ~pen-~itCapper (Courtesy: Kennecott Copper Corp.) FIGURE5.-Chuquicamata Mine, Atacama Desert, Northern Chile. (Courtesy, The Anaconda Company) COPPER

------\ \ \ f ------\ 35 to 40 feet \ \ \ \ \ 0 M IW 150 \ \ \ Scale feet \ _---..__-Toe of bonk Crest of bonk --- Hole locoted 0 Hole drilled Hole blasted Fr~um6.-Plan of Located, Drilled, and Blasted Holm. without secondary blasting. In the ore areas, conveyors, standard-gage railroad cars, large boulders must be broken to a me that the capaclty tractor-type trucks, and tractor- crushing facilities can handle. drawn %rapers. Before WorlGWsr 11, the cost of breaking Bulldozers are used to push materials for gf~undin open-pit mines far exceeded the com- distances to 200 feet; scrapers are used from bmed cost of loading and ha+ng ore. Today 200 to 1,500 feet; trucks are used for distances the cost of loading and haulmg has increased ranging from 600 feet to I mile; and rail whiie the relative cost of brealung ground has haulage is used for distances of more than 1 decreased. It is now about half the total cost mile. Performance with bulldozers ranges from of mining. Loading and transporting ore are 500 to 1,500 tons per shift, that of scrapers closely related. The sizes and number of from about 400 to 1,500 tons per shift, that of shovels used are determined by daily produc- lar trucks from 500 to 2,000 tons per shift, tion, type of material handled, type of haulage, anrthat of rail haulage from about 1,000 to and working wnditions such as height of bank, 3,000 tons er locomotive shift for distances of angle of swm working radius, and clearance. about 3 mLs. On the other knd, selection of hauhge equip- ment is influenced by the type of loading Glory Hole.-In some instances when open-pit equipment used. operations extend to depths that cause the In general, large mines, or tho- with long stripping ratio to become uneconomic, the hauls, have rad haulage; medium-sized mines glory-hole minin method has been used. Thls have truck haulage or truck haulage in com- method has also %een used for mining relatively bination with some other-lype of haulage. small ore bodies or the upper parts of bodies (Rail haulage has been replaced by truck remaining at or near the surface. In glory-hole haulage in a number of the larger mines.) mining, the ore is broken around one or more Some types of auxiliary haulage are inclined raises extending upward from an underground skips (Figure S), vertical skips, inclined-belt haulageway driven below the ore or beneath NOTE : Bidistance from hardtoe to crestline T =dirtonce from hardtoe lo drill hole C.=dirtonee from crest to drill hole

Angle between crest-

meosured with clinometer.

Froua~?.-Vertical Section of Primary Drill Hole.

the ultimate bottom of the glory hole or pit. It burden that caves freely are required also. The is thus a combination of surface and under- method utilizes instability of the ore for caving, ground mining with the ore breaking done on shear and compressive stresses for crushing, and surface but removed thmngh underground gravity for moving the ore to drawpoints. The workings. Under favorable conditions glory- method is nonselective, and lean sections of ore hole mining is as economical as open-pit and waste will be broken up and drawn with mining for the same scale of operations. the ore (fig. 9). Main haulngeways we driven on a level Caving Methods su5iciently below the bottom of the ore so that branching transfer raises may be installed to Caving methods are of three distinct types, connect with a grizzly or slusher sublevel and block, top slicing, and sublevel: so that closely spaced branching draw raises can Block Caving.-This method is amenable to be driven to the bottom of the planned undercut mass production and is efficient and low cost- 10-11). Detailed information about permitting scientific planning, centralized man- the two('T arge block-caving mines in the United agement, labor specialization, and modem States is presented in Bureau of Mines publica- mechanization. The successful use of this tion~.~Figure 12 shows the block-caving sys- method requires detailed engineering study of tem at the Braden Copper Company El the nature of an ore body by systematic and Teniente mine in Chile. detailed exploration and sampling. Adequate Top Slicing.-This is an important modifica- development, preparatory work, transportation, tion of caving, whereby the ore is extracted by ore drawing, and allied mining operations are excavating a series of horizontal or inclined equnlly important. timbered slices alongside each other,'beginning Block caving consists of dividing suitable ore at the top of the ore body and working pro- bodies into blocks of predetermined size and gressively downward. Each slice, when mined undercutting each to induce rock stresses to out, is caved by blasting out the supporting cave and crush the ore to sizes that can be timbers and allowing them to crush, bringing readily handled. Block caving is applicable to the capping or overburden down upon the homogeneous and rather weak ore bodies of I Y. B. Dale. Mining. Milling, md Smelting Methods, Sao Manuel regular outline with enough horizontal area to Copper Cow Pinal Cmnty Ari~.BuMlnesInl. Cuc. 8104 19BZ 1Upp. C.C.POW$. Bhk cav& at Kelly Mine, The Anwnda co:, Butte, 1 cave freely; strong walls and capping or over- Mont. BuMines Inl. Clre. 7758.19SB. 1m pp. COPPER TECHNOLOGY 91

FIGURE9.-Block-Caving Method. (Courtesy. The Anaconda Company) COPPER

J Cmplated mire structure 4 Grilzly drills 5 Finwr mires 6 Undercut Ihel 7 Eorly rmps of mving oltll pillor extraction

FIGURE10.-Block Development, AU-Gravity System. bottom of the slice which has previously been It requires highly skilled miners, more manual covered with a floor or timber mat to separate labor, and more labor expenditures per unit the caved capping from the solid ore beneath of production. and to prevent admixture of waste with the ore. Sublevel Caving.-This method resembles top As successive slices are mined and caved, this slicing in that the ore is mined in horizontal mat follows the minin downward, filling the slices in descending order, so that the ov!r- s ace formerly occupie3 by the ore. The mat burden, or capping, will break up and subslde aP so controls the movement of the caved over- as the ore beneath is removed. The funda- burden and prevents dilution of the ore with mental difference is that the height of slices barren capping. in sublevel caving is greater than for top slicing, Block-caving methods result in some loss of allowing larger output, lower breaking costs, ore and a moderate dilution of ore with waste, and use of less timber. This method, adapted but top slicing, although more costly, is capable principally for certain iron mines in the Lake of virtually complete ore recovery without dilu- Superior region, is rarely used in copper mining. tion, hence is favored for ore bodies of somewhat higher copper content than those to which the Supported Stopes block-caving methods are applicable. Top slicing is also more a plicable, to smaller and The term "stoping" is employed in its broader more irregular ore boges than is block cavmg. sense to mean excavating ore by a series of FIGURE11.41~8her-Gravity Block ThreeBench Raise Design.

horizontal, vertical, or inclined workngs in will stand without support, even in the strongest veins or large irregular bodies of ore or by mms rocks. in flat deposits. It coven breaking ore and In open stopes with pillar sup rt, the length removing it from underground workings (except of unsupported span is Gontro6" ed by leavlng those driven for exploration and development) pillars of ore whose position and size are deter- and timbering, rock bolting, and filling stopes mined by localized ground conditions. fie- for support. quently it is possible to leave low-grade ore Basically, the stoping method or methods within the ore body as pillars, making possible that can be applied to a given ore body depend more complete recovery of the higher grade ore. on requirements for supporting the stope; the Artificially Supported Stapes.-Artificially maximum area or span of back (roof) and walls supported stopes are those in which installation that will be self-supporting during removal of of systematic temporary or permanent support the ore; and the nature, size, and interval be- of eround around mined-mt areas is a Dart of.- tween supports required to maintain the back the%ning cycle. and walls of the overlying and surrounding Shrinkage &'topes.-In shrinkage sto es the country rocks and overburden to prevent their ore is mined in successive flat or incline! slices, movement and subidence. Variations of the working upward from a level or the bottom of principal methods of stopingmay be based on the the block of ore. After each slice or cut, only direction or angle of workin , sequence of enoueh broken ore is drawn off from below to operations, or methods of han 8'ng broken ore. proviae working space between the top of the Naturally Supported Stapes.-Naturally sup- pile of broken ore and the back of the stope. ported stopes are t,hose in which no regular Usually about 35 to 40 percent of the ore will artificial method of support is employed, al- be drawn during active mining in the stope. though occasional props cribs, stub, or rock The remainin ore serves as a floor upon which bolts may be used to hoid local patches of in- to work in ddling the back for succeeding cuts secure ground. Walls and roof are self-sup- and also provides temporary support to the porting. The simplest form is the open stope, stope walls. Forthis reason, shrinkage stopes in wbich the entire ore body is removed from wall are considered a form of artificially supported to wall without leaving any pillars. It is sp- stope. plicable to relatively small ore bodies, as there When active mining has been completed to is a limit to the length of unsupported span that the level above or to the floor pillar, the rest of COPPER

FIGURE12.-Diagramatic Sketch of Block-Caving System of the El Teniente Mine, Sewell, Chile. (Courtesy, Kennecott Copper Corp.) the broken ore is drawn from below, leaving the clined cuts or slices, working upward from the stope empty. Tbe stope ma be filled with level as in shrinkage stoping; but, after each waste later to prevent generaP movement and cut, all the broken ore is removed and waste subsidence or to permit mining of pillars left rock, sand, mill tailings, or other 6lling material between stopes during the first mining. is run within a few feet of the back, providing Shrinkage stoping is applicable to bodies of permanent support to the walls (fig. 13) and ore enclosed between 6rm walls that will not a working floor for the next cut. The term slab or slough off to any extent when left "cut-and-6ll" implies a definite characteristic standing for a considerable time. The method sequence of operations: (1) Breaking a slice of is applied most frequently to relatively thin, ore from the stope back, (2) removing the tabular deposits dipping at angles greater than broken ore. and (3)~, introducing.- 6Uine.- The 50' in which few waste inclusions occur and cycle is re ktitive. which have fairly regular walls. cut-anbl~stmine is a~~hableto mining. A ., - One of the disadvantages of shrinkage stoping 6rm ore enclosed between two walls, one or is the delayed recovery of broken ore that can- both may be weak. In general, it is suitable not be drawn until the entire block has been for mining deposits too irregular for shrinkage mined. Another is that there is more oxidation of sulfide ores than in s stems having immediate stoping and deposits in which shrinkage could withdrawal of ore. dixidation may adversely be employed if it were not for weak walls. affect metaUurgica1 recovery or, in extreme Improved ore-handling and waste-spreading cases, result in a mme he. methods have extended the economic appli- CutadFiU Stapes.-In cutiand-6U stoping cability of cut-and-6ll stoping by comparison the ore is excavated by successive flat or in- to shrinkage stoping, and the method has the 96 COPPER advantage of greater selectivity, better working some sulfide and oxide ores are sufficiently high- conditions, and greater safety. grade for direct smelting, but the bulk of all Rock bolting provides a type of support that native or sulfide copper ores are fist subjected allows cut-and-fill sloping of heavy ore zones to a physical separation of minerals by an with weak and blocky hanging walls that other- upgrading process known as concentration. wise would require squareset timbering. Rock Sulfide concentrates and high-grade ores are bolting extends the time before ground failure, treated in a smelter in a series of pyrometal- requires less time than timbering, permits ex- lurgical steps to produce an im ure (blister) posure of the hanging wall for greater lengths copper, which is subsequently re& ed by yro and heights, and eliminates handling timber on metallurgicd or electrolytic methods. dtive the surface, in the shaft, and underground. copper concentrates are smelted, and the copper All these factors contribute to increased pro- is fire refined. In both smelting processes the duction from fewer working places, thus gangue minerals and other valueless components reducing mining costs. are removed as slag. Byproducts are recovered Timbered &opes.-Timbered stopes are those at one or more of the various steps of concen- in which timber is used systematicall for tration, smelting, or refining. support. The most elaborate system 09th- Concentration is the process of effecting bermg is the square-set method (fig. 14), in hysical separations of two or more mincrals. which the walls and back of the excavation are hneral dressing, ore dressing, bencficiation, sup orted b regular framcd timbers forming a and particularly milling we also part of the skctton encrosing a &ries of contiguous, hollow, concentration process, having slightly difierent rectangular prisirns in the space previously connotations. The plants in which mineral- occupied by the ore and providing continuous dressing operations are conducted are known lines of support in three directions at right as mills or concentrators. angles to each othcr. After liberation of the valuablc minerals from The ore is removed in small, rectangular the gangue, the separation of two or more blocks, usually just large enough to provide minerals from each othcr is posible if they re room for standing a set of timber. Ordinarily sent critical differences in certain physicaf or- the stopes are mined in floors or horizontal chemical properties. Most lmportant in con- panels one above the other, and the sets of each centration and separation of copper mincfltls floor are framcd into the sets of the preceding from gangue are the chemical form, size, densty, floor. Timbered stoping is usually accompanied and surface characteristics of the several by filling, and often in heavy ground the sets minerals in the ore. arc filled with waste aft.er they are installed, The products of concentration are wncen- leaving only a small volume of the stope trates, containing the bulk of the valuablc unfilled at any time. It has become accepted mineral, and tailings, containing gangue miner- quite enerally that, unless the ground is heavy als. An intermediate product known as mid- enougf to require filling for permanent support, dling may be retreated for further recovery of the expense of timbering is not warranted, and valuable minerals before final rejection as other methods should be employed. tailing. Timbered stoping is adaptable to mining Concentration is less costly than smelting regular or irregular ore bodies, where the ore Furthermore. shinnine costs to a distant smelter and/or walls are too weak to stand-even over are reduced b$ ptidu&g a concentrate near the short span-for more than a brief time, and source of ore to avoid freight charges on waste where caving and subsidence of overlying rocks associated mth the ore. must be ~revented. It is the most selective un- Crushing and Grindig.-The first step in deygroun'd rnining inetl~od,itewe is particularly concentration is to crush and grind the ore to su~tublefor mining rk.11, inegulur ore lwdies. such a degree as to liberate the valuable mmerals from the gangue minerals, thus the grain size CONCENTRATING of the ore minerals is an important controlling factor. Hardness, tenacity, brittleness, and The metallurgical extraction processes used in structure influence the cost of grinding and the producing copper metal are based on physical relative degree of sliming (production of ex- and chemical characteristics of the minerals in treme fines) of each mineral in an ore. Crush- ore bodies, such as grain size, copper content, ing and grinding are done only to the dizc nature and content of byproducts to be re- necessary to liberate copper,minerals from the covered, and the type of impurities to be gangue since sliming results in losses. eliminated. Most crushing plants for co per ores obtain Low-grade, oxidized

A Lower dnft ' C 133'4" EARLY STAGE OF STOPING

1133'4" STOPE COMPLETELY DEVELOPED 98 COPPER pieces. This initial reduction is accomplished separation methods, which depend on the use usually by one large gyratory crusher capable, of a fluid su5ciently high in s ecific gravity or at some operations, of crushing up to 2,500 a suspension of a hesppmineraF such as magnet- tons per how and the larger units can receive ite, galena, or ferroshwn in water, to cause the 60-inch boulders weighing 10 tons or more. gangue minerals to float and to allow the ore The 6- to 9-inch product passes to several minerals to settle, or vice versa; (3) tabling, secondary gyratory or cone crushers where it which depends on the differences in s eed of is reduced to a maximum size of 1% to 2 inches. travel of minerals of Merent sizes and iensity, Following screening for removal of material as they are mused to flow in a stream'of water already reduced to wet-milling size, the oversize or air transversely across an inclined, riffled is passed through a tertiary stage of crushing surface that is subjected to longitudiial recip- in higher speed cone-type crushers. The prod- rocating motion. uct is screened, and the oversize is recirculated Jigging, heavy-media separation, and tabling until it is reduced to about # inch. are used very little in copper-ore concentration, Fine grinding is mcomplished in rod and/or because most ores require finer gnnding for ball mills. Although it is possible to grind mineral liberation than the minimum economlc 2-inch-diameter feed to about 48-mesh (0.012 size limit of gravity methods. Most copper inch in diameter) in a single stage, grinding is sulfide minerals are recovered by flotation. A usually cheaper for large tonnage if done in two pilot table, however, is often used as an indi- or three stages when a high, degree of com- cator or guide to help control losses in a flotation minution is requred. Rodmills are used for circuit. coarse grinding, ballmills, for he grinding. Flotation The newer concentrators built in the United States and South America use one open circuit Flotation is a process of wet concentration in rodmill, followed by two ballmills in closed which air bubbles are used to float one kind of circuit with rake classifiers, hydrocyclones or particle from a mixture of two or mqre ldnds hydroscillators, and sand screws, to obtain a of finely divided materisls suspended in water. properly sized flotation feed. Certain minerals may be preferentially wetted Screens and classifiers play an impoftant part by organic reagents in the presence of water so in mineral dressing. Screens and gnzzlles are that they will adhere to air bubbles and float used to bypass material already fine enough or to the surface of the pulp. Other minerals, to return oversize for recrushing. They are usually the gangue, are unaffected and remain most efficient in size ranges greater than suspended in the water. 10-mesh (0.065 inch in diameter); below this The reagents that selectively coat the valu- size various types of classifiers are preferred in able mineral particles are known as collectors. most metallic mineral concentrators. In sulfide flotation these are usually xanthates Classifiers are capable of separating finer or other chain hydrocarbons: Supplementing sizes of materials, into groups according to the action of the collectors 1s a group of re- their settling rate m a fluid, usnally,water, or agents known as frothers whose fu?ction (in air. Of two particles of equal denslty but of conjunction with astation and aeration) is to unequal size, the larger will settle faster; of two create a myriad of small bubbles in the pulp. particles of equal size but differing density, the The bubbles attach themselves to the properly higher density particle will, sett!e faster. Chief conditioned valuable mineral and rise to the ap lications o classification in ,modern ore- surface to form a froth that may overflow or m&ng practice are in closed circuit mth,gripd- be removed mechanically. Frothers in sulfide ing mllls to retufn oversize for regnndmg. flotation are usually alcohols, pine oil,. or ring- Classi6cation also is used to prepare table feed carbon compounds, such as cresyhc acid. in gravity concentration, but tabllng pla s a When two or more minerals of the easier comparatively minor part in modern m&ng floating type are floated together to form one practices. concentrate, ,the process is known as bulk The more important accessories to ore wn- flotation. Differential flotation is the term centrators are conveyors, bins, pumps, feeders, used to describe an operation in wh'icb one or and filters. more minerals are depressed dunng flotation of Gravity Concentration.-Differences in the one or more other minerals, or whefe several density of minerals form the bas.is of gravity different minerals are floated successively inJo concentration proces,ses. The pvci,pal types separate concentrates. The usual differentla1 of gravity concentration are: (1) Jigpg, which separations in copper milling are copper sulfides depends on differences in the set$ing rate of from pyrite, galena fmm sphalente, and minerals as they are carried horlwntally by sphalerite from pyrite. Any one of the sulfides waterflow over a screen bed and subjected to a may be rendered more floatable than the others vertical pulsating action; (2) heavy-media by the current surface modifications, and such TECHNOLOGY 99

modifications are obtained by using a class of Dual Process.-When low ade ores contain reagents known as conditioning agents. Under almost equal amounts of s3 fide and oxidized this class are grouped the depressing, activat- minerals, combinations of leaching and flotation ing, and dispersing agents; the pH regulators; may be employed. In the Inspiration Consoli- and the cleaning agents. dated Copper Co. Dual Process, the ore is first In general, sulfide-mineral particles coarser leached with sulfuric acid in the leaching lant than 35-mesh (0.016 inch in diameter) can- to recover the oxide cop er content, an1 the not be effectively recovered by flotation; washed and drained resilue is treated in the consequently, an ore that is to be floated must concentrator where, after hegrinding, the cop- first be gmund fine enough so that all, or per sulfide values are recovered by flotation. substantially all, the desired mineral is smaller LPF Process.-Along with conversion from than this limiting size. This is aside from underground to o en pit mining at the Ray considerations of liberation, which may re- Mines Division of Reriecott Copper Corp., the quire even finer grinding. mill at Hayden, Ariz., was rebuilt to incorporate To obtain a good recovery and a high- the leach-precipitation-flotation (LPF) process grade concentrate, several stages of flotation for recovering oxidized copper in the open-pit concentration are required. This is conven- ore. This process converts copper oxide to iently, accomplished by employing successive metallic cop er, which responds to recovery by agitating chambers or cells, so that the tail- flotation. $he process starts by making a sand- ings from the first cell may pass progressively slime separation of the rodmill didcharge. The from one cell to the next as the original ore sands are leached in drums with dilute sulfuric becomes impoverished in metal content. The acid and washed counter-currently. The concentrate from the first pup of cells treat- washed sands are ground in ballmills for conven- ing low-grade ores is seldom rich enough for a tional, alkaline, copper sulfide flotation. The final product and is known as a rougher concen- slimes are leached in a tank that received preg- trate, which is re-treated or cleaned in one or nant solution from sand leaching. Sponge iron more stages to produce a cleaner concentrate. is added to the slime pul to precipitate copper, In some instances, the rougher ,tailing may which is then recovered 'L y flotat~onin an acid require regrinding for further hberation of circuit. The LPF concentrate and the sulfide minerals, and in other cases, it may be floated concentrate are joined and pumped to the directly to produce a low-grade scavenger smelter. concentrate, which is often returned to the Segregation Process first rougher cell. The cleaner concentrate is dewatered in a thickener and a vacuum filter, There are oxidized and mixed oxide-sulfide and the dried concentrate is sent to the smelter. ores that are not amenable to leaching with sul- The plant tailing is conveyed by grsvity flow furic acid or conventional flotation concentra- or pumped to a settling pond. Where water tion. The success of acid-leaching oxidized ores recovery is required, the tailings are thickened, depends largely on the amount of acid wnsnm- and the reclaimed water is returned to a large ing constituents in the gangue. If the gangue storage tank. contains significant quantities of calcite or pther Figure 15 is the flowsheet of the Mission acid consuming minerals, acid leaching 1s in- concentrator of the American Smelting and feasible. Where chrysocolla is the predominant Refining Co., near Tucson, Ariz. This modern oxide copper mineral, flotation is impractical installation is one of the more recent world- because there is no commercial flotation process wide. Figures 16 and 17 show the grinding for recovering this mineral. However, research and flotation sections of this mill. at the Federal Bureau of Mines Tucson Metal- With mixed ores, in which both sulfide and lnrgy Research laboratory demonstrated that oxidized minerals occur, treatment depends on the segregation process has merit for treating relative roportious of the two kinds of min- oxidized and mixed oxide-sulfide copper ores, erals. I! sulfide minerals predominate, flo- regardless of the gangue constituents present. tation is used, emplo 'ng reagents that favor The segreption process involves heating the flotation of oxidizer minerals. With such oxidized or mixed oxide-sulfide copper ore wtb treatment, it is usually possible to recover a halide salt, and a carbonaceous material, more than 90 percent of the sulfide copper and such as coke or coal, at approximately 1,400' to 50 to 70 percent of the copper in oxides. If 1,500" F. Basicall , the process proceeds in oxidized minerals predominate, the copper is four stages: (1) 6ecomposition of sodium usually recovered by leaching with sulfuric chloride and formation of hydrochloric acid; (2) the hydrochloric acid attacks the copper acid; ferric sulfate is an effective leaching minerals to form volatile cuprous chloride; agent when the sulfide portion of the mixed (3) the cuprous chloride is reduced to metallic ore has significant value. copper on the carbon particles; and (4) the COPPER ore from mi". 60.1- trucks

FIQUBE15.-Mission Mill Flowsheet. (coartesy, Amerlran Smeltbg and Rehbg Co.) TECHNOLOGY 101 segregated copper is recovered by the conven- natural oxidation of the sulfide minerale by tional flotation rocess. Tests and results of conhual contact with air and water. Some pilot plant ani commercial experience are sulfide ores and mixed ores containmg wp er described in a Bureau of Mines report and a values too low grade to be processed profitafly journal article.' by any other method, but needmg to be re- moved from the mine, can be treated by heap HYDROMETALLURGY leaching. The process consists essentially of piling or dumping leaching ore, without crush- Leaching is the term applied to the process mg or other preparation, on an area having of recovering the valuable metal or metals proper drainage to natural or prepared basins. from an ore by dissolution with an aqueous When possible it may be advantageous to solvent, leaving the gangue or waste material arran e the piles so that the coarser ore will be virtually unaffected. Subsequent recovery of placec? at the bottom and the finer ore on top, the metal or metals from solution is effected aiding ventilation and circulation of the solu- through either chemical or electrolytic precipi- tion. Leach solutions are directed over the tation. For copper these processes are limited iles and allowed to drain through the heap. largely to copper-beanng materials that, he- hesulfide minerals that have been oxidized to cause of gmde, composit~on,or other considera- sulfates are dissolved in the leaching solution, tions, are not amenable to concentration and which collects in prepared basins. Copper is pyrometallurgical extraction. Generally, hy- recovered from the pregnant leach solution by drometallurgical methods are used to treat cementation on scrap iron. After removal of low-grade ores containing native copper, oxide, the w per, the s ent solution is returned to or mixed oxide-sulfide minerals because costs the p'2 es for anotg er cycle of leaching. of other types of treatment are too high or the This method is simple but the reaction is recoveries of copper are too low. Comhina- slow, and years may be required to obtain tions of hydrometallurgcal methodsfor recovery satisfactory extraction. Only large tonnages of oxide minerals coupled with flot,ation or can be profitably treated by this method. sulfate roasting for recovery of the sulfide The process has been the principal method portion have been successful in treating some of recovering copper at RIO Tinto, Spain, mixed ores. for hundreds of years. At one time there was about 20 million tons of ore, occupy- Leaching ing 350 acres, undergoing treatment. In Ari- There are four principal methods used in zona the method is used at the Lavender pit, leaching: (1) Leachmg in lace, (2) heap leach- Castle Dome, Morenci, Silver Bell, and ing, (3) leaching by percofation, and (4) leach- Esperanza mines. ing by agitation. The choice of method de- Percolation Leaching.-Percolation leaching pends on dis osition and grade of ore to be is the method most widely used for commercial treated, as we E as the characterof the associated hydrometallurgical recovery of copper from gangue. large deposits of low-grade oxide ores. Ore Leaching in Place.--Ore bodies that contain charged to a number of leaching vats is suc- sulfide minerals and that are shattered and cessively treated with leaching solution, either broken so air and water have access to the ore by upward or downward percolation, or both. are suitable for leaching in place. The copper Usually the leach solution enters a vat at the sulfide minerals exposed are subjected to natural bottom, percolates upward until the ore is oxidation by alternate and intermittent con- flooded, is held there for a soaking period, and tact with air and water to form water-soluble is then drained and advanced to the next vat wpper sulfate. The leach solution is accumu- where the process is repeated. The flow of the lated in drainage tunnels driven under the ore leach solution in this sequence completes a body or in the lower workings of the mine. single cycle. The number of cycles necessary Leaching in plaee has been successfully applied for optimum extraction depends on the solu- in mines at Butte, Mont.; the Miami and bility of the copper minerals in the ore. If six Ray mines in Arizona; the Eureka mine, cycles are necessary for recovery of the copper Ducktown, Tenn.; the Cronebane mine, County from the ore, six charges or vats of ore would Wicklow, Ireland; and the Aznalcollar and Rio be undergoing simultaneous leaching. Tinto mines in Spain. Particle size and contact time, the two Beap Leaching.-Heap leaching is similar to principal factors affecting leaching efficiency, leaching in place in that it depends on the are interdependent. Most copper ores to be treated by leaching are crushed dry because of ' Rampeeek, Carl. W.A. MoKlnney, and P. T. Waddleton. Treating Oridlml and Mired Oxide-Sulrlde Copper Ores by the Segragstioo the presence of soluble copper minerals, but dr Pmess. BuMines Rept. Inv. 5531 1958 28 pp. Freeman O. A.. Carl ~ampaeek'end'~.0. Evans. Copjwx segregs. crushing below $1 inch becomes uneconomicd tion at tboiake shore ~ine.J. detak, ~ny1x1,pp. 870-372. Higher grade ore may require crushing to FIGUREIfj.-l-Mission Mill Grinding Bay. (Courtesy, American Smelting and Refining Co.) FIGURE17.-Mission Mill Flotation Section. (Courtesy, American Smelting and Refining Co.) 104 COPPER smaller sizes owing to grain size of the copper based on comuelline- economic or technical mineral and the degree of dissemination in the considerations. ' ore. Fine crushing or grindmg is not only Chemical Preci~itation.-Chemical methods ex ensive, but the fine material produced for copper preciphation are those not using re$ uces porosit in the vats and inhibits perco- electrolysis. While there are a number of lation of the i"each solution. In fact, when theoretically possible precipitants, the only one fines or slimes are produced in crushing the ore, that has found commercial importance is iron they are usually separated by classifiers and in tho forms of scrap iron and spon5e iron. treated by suspension leaching methods. This process of precipitation is termed ' cemen- Agitation Leaching.-A itation leaching is tation" and the copper precipitate formed is applicable to those ores t %at cannot be effec- called cement copper. tively treated by percolation or to those opera- Precipitation may be carried out in various tions where efficient extraction is required at a kinds of containers (launders, tanks, towers), rapid rate. Dissolution of the copper minerals depending upon the nature of the iron used. is effected by keeping finely divided ore particles The precipitation reaction, in suspension in the solvent. Agitation is accomplished either mechanically or by forced air and must be strong enough to prevent settling in the tanks. The fine ore or concen- indicates that 1 pound of iron should theoret- trate may be leached on either a batch or con- ically precipitate 1.137 pounds of copper. If tinuous basis. For the batch process a charge sponge iron is used as the precipitant, the of ore is agitated with the required amount of amounts of iron required and cement wpper leach solution until optimum extraction is produced approach the theoretical figures. If reached. In the continuous process, ore and scrap iron is used, however, the nature of the leach solution are added simultaneously, but scrap will regulate the amount needed and the instead of effecting dissolution in a single tank, grade of the cement copper produced. The the ore-solution mixture passes from tank to type of scrap iron used at most precipitating tank, in series, until maximum extraction is plants is detinned and shredded tin cans, and obtained. Pachuca tanks with high lifts are about 1.4 pounds is used to precipitate 1 pound convenient for this type of agitation. Sepa- 31f copper. Whiie the basic reaction for copper rating residual gangue from leach solution and precipitation by iron is very simple, other washing occluded solution from residual gangue reactions may occur during the operation that are done in thickeners. Thickeners are,stand- are related to the acidity of the solutions, the ard equipment for separating a dilute pulp amount of ferrous and ferric iron and copper into a clear solution and a thickened pulp. present, and the rate of flow. These affect When used in series, thickeners provide a con- iron consumption and the grade of copper venient method for countercurrent washing. produced. Free acid and ferric salts in solution can contribute to consumption of iron according Recovery to the following reactions: In current practice there are only two import- H2S0,+Fe=FeS0,+H2, and ant methods for recovering copper from oxidized Fe2(S0,)J+Fe=3FeS04. ores: (1) Direct leaching of ore followed by electrolysis of the leach solution or precipitation The advantages of this method are: (I) Sim- of copper from the leach solution with scrap plicity of operation, (2) effective precipitation iron (cementation), and (2) flotation of oxide from all concentrations of wpper in solution, minerals, leaching concentrates, and electrolysis and (3) precipitation not being affected by of leach solution. impurities in solution. Disadvantages art that The choice of method depends largely on (1) The process does not regenerate acid as in reserves and the size of operation planned. the electrowinning method; and (2) the cement The oxide copper minerals in most ores are copper assays are between 50 and 90 percent readily soluble in dilute sulfuric acid. Electrol- copper, requiring smelting and refining to be ysis of the leach solution produces refined cop- marketable as high-grade copper. per with no further treatment required except Precipitation From Ammoniacal Solution.- melting for casting into shapes. The process Copper dissolved in an ammoniacal solution also regenerates sulfuric acid which is recycled forms complex cup& ammonlum salt that for leaching. The direct operating costs of hydrolyzes readily unless an excess of free producing wpper by this method are said to be ammonia is present. Simple heating to drive as low or lower than heating sulfide ores by off excess ammonia converts the complex to flotation, smelting, and refining. Any depar- the copper salt, which decomposes in solution ture from vat leaching-electrolysis usually is with precipitation of copper oxide. TECHNOLOGY 105

The only hydrometallurgical installation in is considered to ionize as Cut+ ions and SO4-- ions, operation utilizing an ammoniacal leach is that the reaction at the cathode is of the Lake Linden and Tamarack Divisions of Cu+++2(e)=Cu. Calumet & Hecla, Inc., at Hubbell, Mich. In treating ores or tailings, the coarser natjve This reduction reaction is equivalent to that taking place in electrorefinmg. At the anode the oxidizing copper is recovered by gravit concentration reaction is followed by classification an 2' separation of SO,--- 2(e) = SO,. plus 100-mesh sands for the ammoniacal leach. Minus 100-mesh material is treated by flotation The sulfate radical is not stable and immediately reacts with water in the electrolyte to form sulfuric for recovery of the fine native copper. The acid and oxygen according to the following reaction: plus 100-mesh tailing, averaging less than 0.7 percent copper, represents about 10 percent of the original feed. A batch, downward percola- It will be noted that in eleotrolytic decomposition of a tion leaching method is used. Cupric am- solution of CuSO, the solution will be depleted of one monium carbonate is the active leaching agent. equivalent of copper for each equivalent of copper Electrolytic Precipitation.-Electrolytic pre- deposited at the cathode, the solution will be enriched cipitation of copper from copper sulfate leach by the formation of one equivalent of sulfuric aeid, and one equivalent of oxygen will be liberated at the solutions, using insoluble anodes, is termed enode. electrowinning and is the method used by sev- The voltage required for the electrolysis is not the eral large producers for recovering cop er The simple IR drop as noted for electrorefining but includes, principal advantages of the methocf are: (1) in addition to the IR requirements, enough added potential to decompose the CuSO,, plus potential to Electrolytically refined copper can be produced liberate the 0* formed at the insoluble anode. The with no other treatment required; (2) sulfuric latter is referred to as the gas overvoltage. acid is regenerated, sometimes equal to or in Since the net cell reaction is known, the reaction excess of the amount needed for leaching, potential oan be calculated. although usually some makeup acid is neces- CuSO~+H~O=Cu+HBO~+~O,. sary; and (3) the smelting operation is elimi- AH= +56,620 cal The react,ion being endothermic, electrical ene~gy nated. equivalent to 56,620 calories of chemical energy must Grunenfelder explains the reactions of electro- be supplied for the decomposition of one mole of Cu80,. refining and electrowinning, as follow^:^ The electrodes used in electrowinning are Electrolysis can be considered as consisting of two copper starting sheets for cathodes,and some equivalent oxidation and reduction reactions, the type of insoluble anode that will neither react oxidation taking place at the anode, the reduction taking place at the cathode. In electrorefining, the chemically with the electrolyte nor be oxidized, mechanics of the reactions are simplified to the extent either by the current or the oxy en liberated. that the oxidation of an eauivalent of metal st the Antimonid lead anodes are favorki, particularly anode, proportional to the amount of current ~858ing where chlorides and nitrates create no special (Faradny'slaw), is aceompanicd by rhc nrduuiiun of the same rquivaler~iamount of mrtal io~tat the cathode. problems. Anodes may be cast or of rolled to Disrcrard~nnbel~rior* of irnourities. the- cornoosition~ ~ ~-- sheet but are often of grid construction of the elect;olvte remains un&aneed: and the net cell reduce weight and lower anodic current density. reaction, ideaily, is anodic cor&sion and cathodic Cell construction, electrical hookups, and the depmition of equal amounts of the same metal. Be- cause there is no decomposition potential involved, cathode sheets are similar to those used in the voltage required is mainly that needed to overcome electrorefining. ohmic resistance of the electrolyte, or E=IR. The The power requirements for electrowinning process takes advantage of factors which influence are 8 to 10 times greater than for electrore- resistance, such as concentration, temperature, etc., and thus optimum electrolytes and electrolyzing finin but the power costs are largely offset by conditions are chosen. the f ower labor costs. Anode handling and In electrowinnina. the net cell reactions are also scrao remelting. which are maior cost items in equivalent oxidation and reduction reactions, but in eleciTorefining;'are at a minihum in electro- this instance, since insoluble anodes are uied, the oxidation and reduotion does not take place on equiv- wnnlng since the insoluble anodes mav have alents of the same material. Further. then. the a servige life of 10 years. --, ~~~~ source of material underaoine- reaction must bk the The electrowinning process is used to r,ecoyer electrolyte. copper from leach solutions by the Inspuahon Specificially, for the electrowinning of copper from an electrolyte containing copper as a sulfate solution, Consolidated Copper Co. in Arizona; Chile the CuSO, must undergo the oxidation-reduction Exploration Co. at Chuquicamata, Chile; Andes reactions. This again represents the ideal condition Copper Mining Co., Potrerillos, Chile; Union with no complioation of impurities that could be Minihe du Haut Katanga at Jadotville, Repub- present along with the CuSO, in solution. If CuSO, lic of the Congo; and Nchanga Consolidated Copper Mines, Ltd., Northern Rhodesia. Op- erating details for four of these plants are shown in table 12. 106 COPPER SMELTING Roasting for copper blast furnaces is usudly accomplished in moving-bed sintering equip- There are three main types of copper ores- ment to agglomerate and partially roast fine- native copper, oxidized, and sulfide. Since gramed ores and concentrates. most of the world copper production is ex- The wncentrate roduced from some sulfide tracted from low-grade sulfide ores that require ores may be mntroE ed at the concentrator to concentration, the dominant metallurgical avoid roasting before reverberatory smelting. processes for recovering copper metal are In some of the newer smelters roasters were not adapted to treatmg he-grained sulfide con- installed, and at some of the older ones the centrate. The usual concentrate- consists roasters are used as d ers It is apparent that mainly of copper sulfide, iron sulfide, and roasters are graduag being abandoned in gangue, and the purpose of smelting is to cop er ppmetallurgy. separate wpper from the iron, sulfur, and ~fuid-bed roasting, used at some plants gangue. The strong afiity of copper for for roasting copper ores is a new roasting tech- sulfur and its weak a5ity for oxygen, com- nique adapted from the suspended-solids pared with iron, sulfur, and other base metals technique of the petroleum-refinmg industry. of the ore, form the basis for the three major The method consists of partial suspension of steps in smelting-roasting, reverberatory fur- solid particles in a gaseous stream. The gas nacing, and converting. velocities are such that. size segregation of Direct smelting of oxidized ores in blast properly repared feed will not occur. The furnaces began losing importance after intro- entwe flui&ed bed, which is in turbulent motion duction of flotation, wlnch produced a he like a boiling liquid, is substantially uniform material not adaptable to treatment in blast throughout. Copper sulfides can be sulfatized furnaces. Since concentration of low-grade by fluosolid roastmg, making the wpper soluble oxidized ores results in high tailings losses, in water or weak acid. Calcines have consist- direct leaching of such ores followed by cemen- ently been obtained in which as much as 90 tation and reverberatory smelting of the pre- percent of the copper is water soluble, with an cipitates is common practice. additional 5 to 9 percent soluble in &percent The treatment of native copper ores of the sulfur~cacid. At the same time, close tempera- Lake Superior district in Michigan departs ture control allows only 1 to 1.5 percent of the from the general pattern in that there is no iron to go into solution. formation of matte and no converting step. Reverberatory Furnace Smelting.-Reverber- Boasting.-Roasting is a pyrometallurgical atory furnaces are long roomlike structures proces? of heating an ore or wncentrate in an from 80 to 130 feet long and 10 to 35 feet wide. oxidmn atmosphere to effect oxidation reac- Capacities range from 50 to 1,500 tons of tions. 5he object of roasting sulfide ores or charge per day. The fuel and charge are wncentrates of wpper is to oxidize, sulfur and kept se arate Oil, gas, or pulverized coal iron and to move volatile impurities such as is burnelin a &&rate comparbment from which ,.arsenic, and bismuth. Copper and the flame and hot gases pass over the ore. Iron sul des are among the easiest of the wm- Heating of the charge is accomplished by mon metallic sulfides to convert to oxides, with radiation from the roof and side walls rather min+m production of sulfates and other inter- than by direct contact with the hot gases. mehates; furthermore, mixtures of copper and There is little or no reaction between the gases iron sulfides relatively free from inert wm- in the furnace atmosphere and the materia1,on pounds are readily ignited and will roast autog- the hearth; it is possible to get some oxidat~on enously to 6 to 8 percent sulfur without further of the charge by using a large excess of air for ap lication of heat. combustion, but this wastes heat and is seldom !he amonnt of sulfur in the reverberatory practiced. The principal chemical reactions furnace charge determines the grade of matte that take place in the charge of a reverberatory formed. Ores high in iron and sulfur may pro- furnace are between the various constituents duce mattes too low in cop er The proportion of sulfur in such ores is re l.uced before smelting to form a matte and a slag. Reverberatory by roasting them under oxidizing conditions. slags are essentially mixtures of silicates and Roasting practice has developed along two alumino-silicates of iron and lime. In many principal lines-hearth roasting and blast cases, the charge derived from copper-bearing roasting. Various types of multiple-hearth materials is self-fluxing; but usually fluxes, such roasters are preferred in wpper smelters to as limestone, are added to obtain a suitable slag. roast sulfide feed for reverberatory smelting. Analyses of typical wncentrates, mattes, and TECHNOLOGY 107

. -. . . Method of leachtog ...... Upwdpermlatlon...... 5 to 6 days muntermt...... Contlnum w I I tank" Isachlng vat% M~terial~fmnstructbn...... Conoete,leadlined ...... Rslnbroed mcrete, -tic and 1 Pmbuoa tanls, steel, edd-pmaf brl& Uned I , Iangth by width by depth...... 175'W'XO7'O"X18'W' ...... IOYW'XI1YG"XlWO" ... Avemge oharge per taots... tons.. 8 MO...... 8,1 Ciroulatirm...... gpm...... lair- UftBolroulaUon2~, advan08 I

*e. r acidsoluble ...... O.7U ...... Prsotlcsllyl~. %Ed o ...... 0.527 ...... 28appmrimately. sffide cu...... 0.m...... 0.120...... 0.2. Tallinks, pereent: Total Cu~...... 0.148 ...... 0.249 ...... 0.61. Wsterduble Cu...... Raee ...... 0924...... odds CU, sold%oluble...... 0.014 ...... 0.128 ...... 0.5. En,lndeCu ...... 0.134...... 0.099 ...... 0.2. EltraniOn pemt: Tow hu ...... (11.w...... 7I.m ...... 07.6. odde Cu...... 97.343 ...... 70.82...... Sulfide Cu...... 76.Wl ...... 26.8 ...... Starting sheets Dewltlon tanls Starting shests Deposition tanls Etartlng ht. Demsltlon tanks I I Electmlgle to &: I c-vity ...... 1.209...... 1.m...... Fopper ...... grams per Ute.. an0...... 31.1 ...... 46.8 ...... Totd HrSO' ...... do .... IS150...... 1M.6 ...... Flse A,SO, ...... do...... 20.1 ...... Clr ...... do ...... 0.m ...... Total Fe ...... do...... 20.6 ...... 3.18 ...... Ferric Fs...... do ...... 6.7 ...... 0.10 ...... Ferrous Fe ...... do ...... 3.08 ...... Temperst- ...... OC.. M ...... S.8...... 58.2 ...... Electrolyte fmm cells: S lac savity...... 1.148 ...... d"OPpel~~ ..... ~~..~SperU~...... 18.4...... 46.6 ...... Totcd HISO<...... do...... 107.6 ...... Free HBCI...... do...... 1P.B...... Clr...... do...... 0.W ...... Tow Fe ...... do...... 3.30 ...... FerrlcFe...... do ...... 12.0 ...... 0.05 ...... Fmtm Fe ...... do ...... 3.25 ...... Temperature ...... OC ...... 41.8 ...... 48.7 ...... c-t: Total ...... Bmfm:...... cmentdeadty ...... amp~qn.1~6 ...... 11.4 ...... 16.88 ...... Cu.renteWclency ...... perwnt...... 71.65...... 82.W ...... Voltage per tanl ...... 2.16 ...... 0.359 ...... Copper...... LwhIIh...... 1.347...... 0.169 ...... Copper...... lbRw4sy.. 161.82...... Anoda: Matarld ...... Bllster Cu....-- 03.5 Pb 15.0 Eb, Cast mm..... 6 mt18h ...... 1.3 0.15 id. hard had. cu. hgth. wldth, thiokna...... 3'2"X3'4"XM".. 3'3N"XY2!4".. 3'3%"XY2W'... 3'B~"X2'9N" 39lxa"XY5W' XlW'. XX.". sfling ...... 4.W'...... 4%""...... 3%'' ...... 4%"=l~mm... 3%"-Wmm. dght...... wuo&.. 1,100 ...... MMX ...... 200 ...... rn...... 253. Mode of suspension...... Cast lugs...... Cast lugs ...... Coat logs ...... Copper bar, cast-!a. Life in days...... 35...... Cnmalon lt-20 ...... qosls 2 lb of anodenm of cu dapdted. Scrap...... pewnt.. '22.0 ...... 18...... 2a-25 ...... Cathodes: Material ...... Rolled Cu...... Rolled Cu sheel SWlngsheets.. cublanlrs .....-. costarting sheets. Length by wldth by thhknoss .... 3'8"X3'6" ...... 3'8"X3'6" ...... 2'4%"X3'7j4".. 24"X3'IH" ..... 3'1I%"X2'10~" 3'5N"XYBM". XH,". Weight ...... pounds...... 100 ...... BO ...... 68.a...... 11c-120. Mode of suapsion...... Puoched Imm.. Rheted bar... 2 lmw...... Riveted copper Punohed lmm. b" Replaoed after(?)days ...... 1 7 ...... 1 walghtstartingsheet.... pound8.. 1i:ii::::::::::::l 18-14 ...... leii:::::::::::: Fernmt starting sheets used for 1 15...... 1 ...... I 20.n ...... Imw,.- au.,,,--.- - -.ara. . Deposition tank% Number ...... 17-18 ...... 120 ...... 51 ...... Lea@ by width by depth...... %'W'X4'W'X4'3" 1W3"X2'IW'...... Number ol anodes, eathoda ...... 98, 88 ...... Z 24 ...... Electrlcmoneotion ~btmlledCu

Material of construction Reinforoed mn- mete lined with 7 per- at-Sbled. ~ireu~~tlon...... gpm...... 10...... See footnotes at end of table. 108 COPPER

- Chile Erplwstion Commy. Choqoloamsta, ChUe ~~th~dof~ding...... sto oh permladon ...... Leaching vats: ~aterlatormnshlct1on ...... Rslnlomed mnmte med with 4" dny. aphalt sand rmdure...... Mgth by wldth by depth ...... IM'XllWX(18.5' and 19.5') ...... Amage charge per ....tom.. 13,181...... 3,m...... c-tion ...... - ~~ O"~Gg?...... co add saluble ...... OdZ,...... BadeCu ...... Z\allings, percent: TdCu ...... Watersoluble Ou ...... odde Cu, soldeoluble...... Bolllde cu...... Ertmtian perosnt: Total 6" ...... 81 W3 OxIda Cu...... w1a7...... Boltlde Cu...... 17:?SO...... starting sheets I Deposition taks I Retloed I iststage, I Mstage. 1 Plating down, I Wholebousp, m.083 19,181 3,838 U3.m

Electrolyte to cells: Spe~Lflogavlty ...... 1.130 ...... 1.225 ...... 1.115 ...... 1.110 ...... 1.110 ...... 1.114. copper...... g-w~ter.. 81.6~1...... a.10...... a.96...... m.?~...... 17a6...... P.M. TotalE*O< ...... do.... 83.16 ...... m1.H .....-.....91.74 ...... 86.18 ...... 8.22 ...... 81.67. PmHa01 ...... do .... 8.81 ...... l'i3.a8 ...... 67.83 ...... 66.77 ...... 58.111 ...... 68.14. Ch...... do.... 0.819 ...... 0.04 ...... 0.09 ...... 0.08 ...... 0.12 ...... 0.09. TotalFe ...... do.... 2.81 ...... 3.U ...... 2.87 ...... 2.82 ...... 2.68 ...... 2.8. FemioFe ...... do...... 1.16 ...... 1.69 ...... 1.05 ...... 1.16. FmmFe...... do .... 2.81 ...... 3.11 ...... 1.71 ...... 1.D...... 1.64 ...... 1.69 Temperatore ...... OC.. 28.3 ...... 47.6 ...... 3'2.6 ...... 34.2 ...... 33.4 ...... 8.4. Ele&olyte from calls: B iBcg,%vLty...... 1.127 ...... 1.225...... 1.110 ...... 1.198 ...... 1.W...... l.lC8. Gper...... g-perliter.. 8.766 ...... 52.10 ...... 18.71 ...... 15.96 ...... 5.7S ...... 18.38. TotalII90~...... do.... (a.75...... B1.H ...... 85.51 ...... 81.m ...... 8.23...... 96.07. FrseE9O, ...... do .... 40.10 ...... 123.38 ...... 66.83 ...... 71.04 ...... 76.65 ...... 67.M. CI, do.... 0.810 ...... 0.04 ...... am...... o.10 ...... 0,la ...... 0.08. TotalFe ...... do .... 2.88 ...... 3.44 ...... 2.81 ...... 2.83 ...-...... 2.8...... -- 2.67. FdcPe...... do.... 0.73 ...... 1.88...... 1.85 ...... 1.70 ...... 12% FerrausFe ...... do .... 2.16 ...... 3.44 ...... 0.98 ...... 0.88 ...... 0.99 ...... 0.81. Temperatme ...... *C.. 28.5 ...... 47.6 ...... 36.0 ...... 36.4 ...... 983...... SB.2. c-t: TOW...... amyrs?.~:: 25.318 ...... 26,080 ...... 24,538 ...... 28,156 ...... 28,057 ...... - 24,538. Cmtdensity ...... amp sq It 16.22 ...... 21.2 ...... 14.W ...... 13.40...... 1b.M ...... 14.20. ~-te~~eienc~...... 86.88 ...... 81.19 ...... 8.33...... 64.~...... 81.13 ...... e4.87. voltagepert& ...... 2.12 ...... 0.15...... 2.m ...... 1.86 ...... 2.017 ...... 2.m. cappe...... MVR,.. 0.832 ...... 0.208 ...... 0.891...... 0.882 ...... 0.851 ...... am. Copper ...... Ib/kw&y.. 25.76 ...... 11CIZ...... 26.80 ...... 2881 ...... 26.X ...... 16.67. Anodes: MaMd...... PMb-Aq...... Bolubleanode ... Pbsb-Ag ...... Pb-Sb-Ag ...... PMbAg...... Pb-8bAg. ugth,width, thloknw ...... YZ$~"X~IWX 4'~"~3'1%".... ~'~"xTw'x I'I"XZ'W'X 4'l"x~'w'x 4'1''XTW'XMdr. Ma". M d'. MI". MI". Sping ...... Inch.. 3...... 4% ...... 3 ...... 3 ...... 3 ...... 8. M%ht ...... pound.. 310 ,...... 783 ...... 210 ...... 210 ...... 210 ...... - 210. or suspension...... cumsen ...... cast C" luas .... curn ...... cuinsen....-... cuinatnt....---- C" Insen. Libin day8 ...... 19...... 8oap...... perwnt...... 20 ...... Csth*: Mama1...... Cu bm...... Cu bl& ...... Cukt...... Cusheet...... Gushset...... Cn shest. Length by wldth by thioknm.... 4'I"X3'I"XX".. 4'1"X3'I"X$4".. 3'W'X4'@" ...... 3'G"XI'N' ...... 3'VrX4'W' ...... 3'0"X4'C". Weight ...... ,...... pound.. 1M...... 1M...... 1M...... 1% ...... LM ...... 150. Mode of suspem~on...... Rlvcted to bar.. Riveted to bar.. 2 Imps punched. 2 Imps punched. 2 lmpa punohed. 2 lmP punched. Beplsoed after (7) day8 ...... Btrlpped daily.. Stripped day.. 5-8 ...... 54 ...... ;.. 54 ...... 5-3 Weht sthgsheet ..... pound.. I1...... 16...... 11...... 11...... 11...... - 11. Percent starting sheets usad for 18...... 18...... 19...... 19...... 19...... 19. Imps, mp,etc. Depaldtion tanks: Nomber aperags ...... 72.48 ...... 83.73 ...... 616 ...... 152...... 67.67 ...... --.-€35.67. Length 6y vldth by depth ...... IW2"X3'I"X lW2"X3'11"X 18'2"XIll"X lWY'X3'LI"X lWT'X3'11"X 19'2"X3'Ll"X 4'10". 4'10". 4'10''. 4'LW'. 4'10". 4'W N~~~~OIBOU~P~,C~~~O~~S...... a,62 ...... 48 47 ...... 73 72 ...... 73, TI ...... 73 12...... - TJ n. Eleotriom1111ectlan...... Whitehead ...... ddkw...... dhitehesd ...... Whitehead ...... dhltehesd...... dhitehead. M8te&l0feomhlctio~...... Mastic-lined Mastihlioed Maticlined Matlelined Masticlied Mastblined mnuste. mnorete. oonerete. -mete. mnwete. mnmte. Clrmlallon ...... gpm.. 36.41...... &S ...... 234 ...... 376 ...... 933.7 ...... 24%

1 TWOelectdeal circuit. each of en tsmh in serls. six motmgenerstn. Bnuce: Mantell, C. L. Eleolmchm. Eng.. McClraw-Hill Bmk Co., sets: 2X4,aQ amp ~a)volt. (I spare). FIV~generators of 4,m amp, Inc., ~ew~ork. 1880, PO.man. m,m amp for each cirmit. slags at smeltera in Montana, Utah, and Ari- Air under low pressure enters the furnace zona are shown below: through tuyeres near the bottom of the furnace above the hearth. The tuykes are pipes 4 to cu Fc S, SIC,. Coo, Ahh. 6 inches in diameter, spaced 10 to 18 inches *A ;Rt.$nl *mu ~ntpcrccnt pnmt Concentrate.. 24.8 23 33 12.9 ... 2.5 apart along both sides, and connected with a Matte...... 45.0 23 24 .... -...... bustle pipe that carries the main air supply. Slag.... -... . .56 42.5 .... 34.5 5.8 6.3 The lower part of the furnace walls usually Concentrate.. 31.3 22. 7 29.8 14 5 ... .09 Matte.. -..-. 43.4 22.0 25.0 ...... consists of steel water jackets, while the up er Slag .... -.... .43 34.5 .... 39.2 6.8 4.8 part of the wds may be constructed of eitR er Concentrate.. 23. 3 24. 2 31. 0 9. 4 2. 4 2. 4 refractory brick or a second tier of water Matte-...... 31. 6 35. 0 25.0 ..--...... jackets. In copper blast furnaces, the crucible Slag .--.-..-. .40 34.2 .... 37.0 5 7.2 Concentrate.. 15.4 31.0 36.9 11.0 ..- 4.3 is used as a collecting trough from which the Matte-...... 27.2 40.7 24.0 0.8 ... 1.3 matte and slag flow to a forehearth or settler Slag .-.--.- - - . 34 36. 1 1. 3 37. 6 3. 5 9. 6 in which the slae rises to the to^ and is removed almost continud~y. The reverberatory furnace is constructed on a Blast furnaces are still used at the following massive and heavily reinforced concrete founda- plants: Union Miniere du Haut Katan a, tion that supports the sides and end walls and Elizsbethville, Republic of the Congo; The lfio encloses the furnace bottom. The hearth is 24 Tinto Co., Spain; Mount Lyell M. & R. Co., to 30 inches thick and is lined with a refractory Ltd., Tasmania; Tennessee Corp., Copperhill, material such as silica or magnesite brick. The Tenn.; Falconbridge, Ontario, Canada; Phelps sidewalls are usually of silica brick, but if a Dodge Corp., Laurel Hill, N.Y.; and Interna- magnesite hearth is used a layer of chrome tional Nickel Co., Coniston, Ontario, Canada. brick is laid to separate the acid sidewalls from Electric Furnace smelt in^.-Electric smelting the basic bottom. The more recent reverberatory of copper concentrates to matte is uses furnaces have the Detrick-type suspended arch, when the cost of electric power is less than coal which permits easy fettling and arch mainte- or other fuels. The chemistry of the electro- nance. Charge hoppers are arranged in a row thermic reduction is essentially the same as in above and along each side of the furnace. Slag reverberatory smelting; interaction of the com- is tapped from the up er end of the furnace into ponents of the charge is the same, with forma- launders leading to sP ag cars; matte is tapped tion of matte and slag and elimination of some from near the burner end into ladles for transfer sulfur as sulfur-dioxide gas. to the converten. The Bolidens Copper Co. in Sweden operates Blast-Furnace Smelting.-The copper blast an electric matte smelting furnace that is similar furnace is used mainl for ores more than 1 inch in design to the reverberatory furnace. It is in diameter, althougt fines may be treated if 77 feet long by 20 feet wide with six Soderberg sintered. A few plants still use blast furnaces electrodes installed through the centerline of because they are useful under certain conditions, the roof. Each electrode is 3.9 feet in diameter but they account for very little of the world and is connected to a 2,000-kva transformer for copper supply. a total furnace energy of 12,000 kva. Calcines from the roasters are charged di- The blast furnace is essentially a Ion , nar- rectly into the furnace through charging pi es row, water-jacketed upright shaft. The 7ength in the roof. Three tapholes for drawing off si' ag of the furnace varies considerably, being pro- are at different levels at one end of the furnace. portioned according to capacity. The size of a The slag, which is tapped almost continuously, furnace is expressed in terms of the dimensions flows through covered launders to a granulating at the tuyere level. The width, being limited plant where it is sprayed by jets of water; the by ability of the blast to penetrate the charge, mixture of granulated slag and water is pumped is usually 44 to 48 inches, though some furnaces to the slag dumps. Matte is tapped at a lower are as narrow as 30 inches and others as wide level through three holes at the opposite end of as 56 inches. The molten products, slag and matte, collect and are drawn off at the bottom, the furnace. The matte averages approxi- and new material is charged at the top to keep mately 35 percent copper; the slag, 0.3 to 0.5 the charge-level relatively constant. percent. Blast-furnace fuel is almost invariably coke, Some advantagcs of electric smelting have charged with ore and flux and ranging from 13 been noted as follows: to 17 percent of the charge. Thc coke burden 1. Thermal efficiency is greater than that of a rever- beratory furnace because there is no volume of high- may be adjusted to control the degree of sulfur temperature combustion gases carrying away much of elimination, hence it is seldom necessary, unless the generated heat. sintering is required, to roast ores in advance of 2. There are no combustion gases to dilute the sulfur dioxide (SO2) gas, and the smaller amount of gas is matte blast-furnace smelting. much richer in SO2. 110 COPPER 3. Outstanding over the reverberatory furnace is the necessary, especially during the blister stage. ability t,o reduce magnetite in hot and cold converter slam returned to the furnace. In the electric furnace Each tuydre is equipped with a special valve the electrodes can be lowered to increase the heat of for punching the tuykre without dropping the the bath; by addin fine pyrite end siliceous material, air pressure and allowing the molten bath to the magnetite (Fefh) is reduced to FeO which com- run out through the tuyde. Mechanical bines with the slag. tuydre punching is employed at some plants. Converting.-Converting is the final stage in Air is supplied at 10 to 20 pounds per square smelting copper sulfide ores or concentrates inch, and the amount required ranges from and is accomplished by blowing thin streams of 160,000 to 200,000 cubic feet per ton of blister air through the molten matte (product of the produced from 40-percent matte. reverberatory or blast furnace) in a refractory- Two types of converter linings arc used in lined converter. modern practice-basic (magnesite) and acid The first or white-metal stage of converting (silica). Basic linings are almost univenally is rapid oxidation of the iron sulfide in the preferred, chiefly because of lower operat,ing matte to iron oxide and sulfur dioxide. Enough and maintenance costs. Basic linings have a silica is supplied to form an iron silicate slag. much longer life than acid linings, converting The copper remains as co per sulfide untd most 2,000 to 2,500 tons of copper per ton of lining, of the iron has been oxigzed. When slagging compared to 10 to 100 tons with the acid type. is complete, the slag is poured off, leavin Other advantages of the basic lining are use of molten copper sulfide-known as white metaK larger vessels, ability to convert low-grade at this stage. Blowing is then continued in the mattes with relatively little lining consumption, second or blister stage to oxidixe the sulfur of and less handling of the shells. The disad- the white metal, leaving metallic copper. The vantages of the basic lining are excessive first stage is strongly exothermic and raises the punching of the tuydres necessitated by forma- temperature of the bath high enough to form tion of magnetic iron oxide about their mouths, slag and to provide enough superheating for the greater time required for lining and repairing, second stage, which does not liberate as much and excessive blowing-out of fine, siliceous ore heat. during charging of the flux. A low-grade matte produces a larger amount Converter slag contains 2 to 5 percent copper of slag to be retreated for copper recovery and and is returned to smelting furnaces for re-treat- requires more silica than a high-grade matte; ment, where its high-iron content is generally but if the matte is too high in cop er and too an aid to fluxing. low in iron, too little heat may be {berated to maintain the process. Heat can be supplied When the converter cycle is finished the con- with pulverized coal or fuel oil to convert verter is tilted to discharge the copper metal copper mattes that contain as much as 60 per- into ladles in which it is transferred to the cent copper. Table 13 shows analyses of matte anode furnace and casting machines. At small treated and converter slag produced at forty plants casting molds are assembled on trucks, worldwide copper smelters. which are passed in front of a launder, receiving There are two principal types of copper the copper directly from the converter. converters, the Pierce-Smith and the Great Due to the rough upper surface when Falls. Both types are mounted on trunnions solidified, the product of the converter is known for tilting to receive the charge and pour off as blister copper. The rough surface is a result slag and metal, and both have a row of tuyhs of the expulsion of gsses, largely air and sulfm- in the rear connected with a wind box to intro- dioxide, as the molten metal cools. duce air into the charge. Of the 40 plants Blister copper contains most of the precious shown in Table 13, 29 use Pierce-Smith (hori- metals of the charge and minor quantities of zontal) converters, 7 use Great Falls converters certain other elements; hence it is invariably (upright). Most of the larger plants use 13- refined before being marketed. b 30 foot, Pierce-Smith converters, but 14 A 13- by 30-foot, Pierce-Smith converter p?kseport having converters about 10 to 12 holds 200 tons of matte and at 1.2 cycles for feet in diameter and about 20 feet or less in 24 hours has a capacity of nearly 100 tons of length. Figures 18 and 19 show the pouring copper per day on 37-percent matte. Within of blister copper at United States and U.S.S.R. moderate limits, the capacity varies 5 tons with smelters. each 1-percent variation in matte tenor. A Tuydres range in diameter from 1% to 2 inches; in the newer plants the larger sizes are 12-foot-outside-diamcter, Great Falls converter preferred. They are placed 8 to 12 inches may take an initial charge of 10 tons of 40- apart and high enough above the bottom to percent matte and by four successive blows clear the level of the metal at the fmish of the and charges may yield 20 tons of blister copper blow. Frequent punching of the tuyhres is per 6 to 12 hours or 40 to 80 tons a day.