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Home , Agate, Agate (nuclear test), Mineral collecting, Peridot, Petrified wood

PRODUCTION IN

by Ken A. Phillips, Chief Engineer

Mineral Report No.5

ARIZONA DEPARTMENT OF MINES AND RESOURCES ARIZONA DEPARTMENT OF MINES AND MINERAL THE ARIZONA DEPARTMENT OF MINES AND MINERAL RESOURCES RESOURCES

The objective of the Department is to promote the development of Arizona's mineral resources. This is accomplished through technical research, field investigations, compila­ Leroy E. Kissinger, Director tion of information into a mineral occurrence data base and disseminating information through publications, personal contacts and seminars.

The Department's engineers and assist mining and exploration com­ panies, prospectors and others interested in Arizona's with mineral processing, Phoenix Office: Tucson Field Office: mineral land acquisition, exploration, mine development, financing, government regulations Mineral Building, Fairgrounds 416 W. Congress, Rm 162 and mark ting. Phoenix, Arizona 85007 Tucson, Arizona 85701 (602) 255-3791 Office open Monday and Tuesday The Department is a service agency and does not regulate, tax, or require any type of Toll Free in Arizona: 800-446-4259 (602) 628-6340 registration. The agency provides assistance that is tailored to meet the differing needs of the public. The following is a partial list of services which the Department offers: • Maintain a site specific data base of unpublished reports and maps that includes 5,000 mine files and indexes of 10,000 computerized Arizona mineral occurren­ ces. • Maintain an information bank and library of mineral and mining information including a mine map library (hard copy and microfilm), government publications, BOARD OF GOVERNORS periodicals, and unpublished master and doctorate theses. • Gather and disseminate information on commodities and markets. • Suggest target areas for possible exploration activity. Clifford B. Altfeld - Tucson Chairman • Suggest prospects and individual properties for study and acquisition. • Assist individuals and companies in their dealings with State regulatory agencies to facilitate their mining and exploration activity. Roy Miller - Phoenix Edna Vinck - Globe • Produce publications in the form of mineral reports, annual directories,technical Secretary Vice Chairman reports, annual mineral industry surveys and information circulars. These include Laws and Regulations Governing Mineral Rights in Arizona, Directory of Active Mines in Arizona, Manual for Determination of Status and Ownership of Arizona Arthur H. Kinneburg - Phoenix C. 1. Hansen - Tucson Mineral and Water Rights, and others. A current listing of the Department Member Member publications is available upon request. SPECULARITE CONCLUSION

Specularite or specular is the lustrous steel gray variety of the common oxide Prase, gem smithsonite and alabaster have also Department of Mines and Mineral Resources mineral hematite. It is also known as "Alaskan been found and produced at various times. Mineral Building, Fairgrounds ". It occurs in hydrothermal and Even though Arizona is thought of as a non­ Phoenix, Arizona 85007 replacement deposits in a number of locations. ferous metal producing state, both the value (602) 255-3791 Toll Free in Arizona - 1-800-446-4259 Specularite of gem quality is collected from the and beauty of Arizona's are very Bouse area of western Arizona and cut into important to the State and its mining industry. cabochons and beads. Arizona's number one gemstone mining status will continue to be dependent on the popularity APACHE TEARS of its gems.

Apache Tears are a rounded, naturally occur­ opaque to translucent, black to gray GEMSTONE PRODUCTION globule of structurally homogenous volcanic glass. They occur as both nodules and as perlite nodules. They are locally abun­ IN ARIZONA dant in the commercial perlite deposits in the Superior area of central Arizona. After being tumbled and polished they are sold as or used in assorted jewelry. One perlite producer has made a business of operating a fee collecting area open to the public.

ONYX

Gem , also called Mexican Onyx, is the Mineral Report No.5 banded variety of dense produced by springs. To command a market as gem material the onyx should be dense, banded with multi­ colored or multi-shaded bands and able to take by Ken A. Phillips, Chief Engineer a good polish. Such onyx is produced from at least two quarries in Arizona. Lessor quality onyx from these same quarries is sold as January, 1988 decorative stone.

6 mercial gem quality is collected from the Maricopa Mine at the southern end of the Mazatzal Mountains in central Arizona. The Arizona is probably much more famous for its deposit is popularly called the Four Peaks garnet than are Arizona's famous. Amethyst Mine and is a private patented claim Gemstone literature of the first three decades of within the Four Peaks Wilderness in the Tonto this century highly tout the gem garnet National . Material thus must be packed of northeastern Arizona. The small deep red or flown out from the property. Although garnets were often referred to as Arizona officially idle and posted against trespassing, . Pyrope garnets occur and are col­ top quality material continues to be removed lected from the area of Garnet Ridge about 5 from the deposit and finds a ready market in miles west of Mexican Water just south of the both the commercial and hobby industry. The border and at Buell Park about 10 miles best amethyst from the Four Peaks locality is north of Fort Defiance. Both localities are on considered to be as good as the best found any the Navajo Indian Reservation. Commercial where in the world. The deposit has been production of pyrope garnet from these areas is described as solution cavity fillings in not known but it is suspected that small . Amethyst is also collected from a amounts are collected by local residents and number of other sites in Arizona by hobbyists sold to hobbyists through the trading com­ and a small amount also finds it way into retail panies active on the Reservation. The best are rock shops. over 3 carats and of very good quality. Com­ mon garnet occurs at many localities in Arizona, some of which are famous for their FAMILY MINERALS specimen grade material. Spessartite garnets occur as accessory minerals in numerous peg­ Gemstones in the quartz mineral family matites throughout Arizona. Wine red gem produced in Arizona not already discussed in­ quality spessartites up to an inch in diameter clude the various and . These have been found, but reports of such occurren­ varieties occur in nearly every ces are very rare. conceivable color and pattern. They are often given descriptive names such as plume , crazy lace agate, or roses, or AQUAMARINE locality names such as Cave Creek or Burro Creek agate, all names that to the trade Aquamarine, the clear, light blue gem variety indicate a particular gem material. The rough of has been collected from at least one gem material is typically mined by hobbyists locality in Arizona - Pima County. No com­ for their own use and the excess sold to mercial production has ever been attempted. wholesale/retail suppliers and cutters. Addi­ Aqua-marine of cabochon cutting quality does tional production is by transitory operators who not need to be clear. Such material could be contract mine for independent brokers. produced from a number of beryl properties as a byproduct of hand sorted and hand cobbed beryl production.

5 lands to 250 pounds plus one piece per year. Therefore, commercial production must only come from private lands. Quality material is Opal is an amorphous mineral species of distributed over large areas of private range dioxide which occurs as a mineral gel. The land in the northeastern part of the state where well known gem variety called precious opal is it is collected and excavated by property translucent with a internal play of colors some­ owners or processors who lease times called fire. Milky blue precious opal TABLE OF CONTENTS rights. At least one land owner has an in­ has been produced from a deposit in southern PAGE tegrated collecting-processing-marketing Arizona where it occurs in rhyolite. Produc­ Occurrence Map ...... operation. tion has been by claim owner-miners and sold Abstract ...... 1 Gemstone Production...... 1 directly to cutters and hobby . ...... 2 Gem petrified wood is cut and polished into a Quartz ...... 3 variety of gem objects, some rather large. Ob­ Garnet...... 3 jects or products include such items as tumbled Aquamarine ...... 3 and polished pebbles, cabochons, pen-pencil Specularite ...... 3 set bases, clock faces, and coffee tables. Fears Fire agate is the cryptocrystalline variety of Apache Tears ...... 3 in the early 1900's that petrified wood would quartz known as chalcedony in which the in­ Minerals...... 4 all be exploited led to the creation of the clusion of iron oxides causes a fire or play of Opal...... 4 Petrified Forest National Monument. This Na­ colors much like that exhibited in precious Fire Agate ...... 4 tional Monument contains an excellent display opal. Fire agate occurs at a number of Amethyst ... ' " ...... 4 of petrified wood in its natural mode of occur­ localities in Arizona where it is either merely ...... 5 rence. collected as residual pieces on the surface or Petrified Wood ...... 5 mined by simple open pit methods. The fire Onyx ...... 6 Conclusion...... 6 agate most often occurs as a secondary chal­ COPPER MINERALS cedony "cement" filling spaces between basal­ tic boulders in near surface flows. The In addition to turquoise a number of other flows are drilled, shot with quarry type ex­ secondary copper minerals are used as plosives, and the shot material dozed into shal­ gemstones. These include azurite, , low heaps. The heaps are watered to wash fines , shattuckite, ajoite, tenorite, and from the broken material and to enhance the chalcopyrite in schist. These copper minerals visual recognition of any exposed fire agate. find their place as gemstones because of their Fire agate is then collected by hand with any brilliant colors and ability to take a fine polish. excess matrix material removed by hand cob­ When naturally coated with sufficient silica or bing. Cleaned, graded rough material is occurring as silicified specimens, these marketed internationally to cutters. The minerals are also very durable. Commercial Arizona industry consists of three or four com­ production is as a byproduct of active large mercial mines and a couple of fee collecting copper mines, typically by contractors and areas open to the public. from a few small copper mines that produce gem and specimen material only. AMETHYST

Arizona is one of the few, if not the only, state which produces gem quality amethyst. Com-

4 Turquoise is or has been mined from a number peridot from the Peridot Mesa area of the San of Arizona copper mines as a byproduct, usual­ Carlos Apache Indian Reservation east of ly by contractors. Some contract operators are Globe is some of the finest quality material in little more than commercial collectors of the world. Further the deposit is one of the material while others run essentially a full scale most prolific. The crystals occur as open pit mining operation, independent of, but single crystals and as pockets of granular mas­ simultaneous with the active copper mine. ses in an olivine basalt flow. Commercial Mining is done by the usual open pit methods production of peridot consists of individual using mechanized equipment until a vein, lens pieces 1/4 inch in diameter and larger. In­ or pod of turquoise is encountered. At that dividual gem quality crystals of over an inch in point the turquoise is carefully extracted using diameter have been produced. Mining is done hand methods. by shallow drilling and blasting of productive zones followed by hand breaking and hand Once mined, the rough turquoise is sorted and screening and sorting. Mining is done by in­ graded. The best quality material is sold by the dividual Indians and occasionally by small piece, and the remainder sold or processed for tribal contractors. Production is sold through sale by the pound. Standard terminology has local and Phoenix brokers. Peridot is tumbled been developed to describe natural and or faceted to produce commercial gems for processed turquoise. Natural turquoise is that setting or stringing. material of sufficient hardness and acceptable color that it can be cut and polished into usable gemstones. Stabilized turquoise is material of PETRIFIED WOOD acceptable color that has been treated to en­ hance hardness and durability. Treated tur­ Petrified wood or wood, although occur­ quoise is material in which both color and ring in nearly every state, is best know as an hardness has been enhanced. Durability is im­ Arizona gem material. Petrified wood probab­ proved by the addition of hard plastics orresins. ly ranks third in value as an Arizona gemstone. Turquoise of a quality too low to be marketed Petrified wood is a fossil in which a mineral, as either natural, stabilized, or treated is used to usually silica, has replaced the original cellular produce reconstituted and artificial substitutes. structure of the wood. Often the internal ring structure and even the external bark and knot Turquoise is used in jewelry in the form of cut appearances remain. That petrified wood in and polished cabochons, tumbled and polished which replacing silica has taken on various free form nuggets, and carved objects. It is colors or in which the ring structures are well ei ther set in silver or drilled and strung as beads. preserved finds value as a gemstone. It is the nnml'lTV stone 11 seci in trl'lciitionl'll ~ oJ ------Navajo, Hopi, and Zuni Indian jewelry. Petrified wood occurs in all Arizona counties, but that occurring in Navajo and Apache Coun­ ties in northeastern Arizona supplies nearly all PERIDOT of the gem market. Pieces as small as 1/4 inch pebbles to trunk sections larger than 5 feet in Peridot ranks second to turquoise in value of diameter find use in the trade. Federal law Arizona gemstone production. Peridot is the limits the amount of petrified wood which can gem variety of the mineral olivine. Arizona be collected by any individual from public

3 world. The State's and climate have making Arizona the number one ranking combined to make it the number one rockhound gemstone producing state. GEMSTONE PRODUCTION IN ARIZONA state in the Nation. Turquoise is prized for its color and its use in The State's gemstone industry consists of 40 to traditional Southwestern American Indian r-----·-----·--·-----;--·--·--·--·--·--·--.--·-:.--·--·--·r-·i-~:;:_~:;_·-! I.. i i:'I I 50 commercial operations including mines, jewelry. The mineral is colored by the copper I' • brokers and processors with a few hundred present in the structure. , a beautiful I l, people earning a full time living from the busi­ green gem mineral, is very similar in composi­ 1 ness. Mining methods range from the most tion and appearance to turquoise but lacks the , _.' .J ,1 J , simple to state of the art open pit technology. copper. Varying amounts of impurities can ..... - ..... , I , , '\' .,.1 However, all gemstone production has in com­ cause the color of turquoise to vary from blue \ '-" \ 1 \ I mon the need for, at some point, very selective to green, reddish brown, chocolate brown, ; COCONINO !A PACHEj mining using hand sorting and cob bing. The violet and white. When pure and solid, tur­ I , I , -'1 i simplest methods amount to no more than col­ quoise has a hardness of 6 and a specific gravity 1 I I 1 MOHAVE !...... lecting of suitable material from the surface of of 2.7. Turquoise is generally massive which \ ; ...... I I • Turquoise _ ._ •• _ the ground. Brokers play an important role in is the form used in jewelry. \ • Obsidian , ; .. ~ the State's gemstone production. Much , .fire Agate jN A V A J a i production is done on a casual basis by part Nearly all the important deposits of turquoise I l...."_"_j \ • Aquana~ine i time and itinerant operators without a regular are located in the arid desert regions of the " _ ••,. etrified wood I market. Broker-buyers provide both a market world. Turquoise is a secondary mineral. It is copper Minerals • \\ .!. • Jasper , iI for the producer and a steady source of supply derived from other minerals under the action of \ Agate • : i to the jewelry fabrication industry. Arizona ground water, surface water, and reaction with ", ; '( A V A P A I ..;-.. _.. , gemstone processors include gem cutters and elements from the air, notably . .}. .. - /"---! • OnyX i ...... , .. - ! ,.,,'" "-., i :per : __• • Blae! i polishers, manufacturers of such items as pen­ ! _ : .,._.. \ I , .Specularltef-··---_., .Garnet • ----; 1_.. _--_---; i pencil bases, and stabilizers and treators of Early production of turquoise was from mines I • ". I OnyX. • , i " • Apache Tears ~ Alllethyst .Tlger Eye !. r J-..-i turquoise. Traditional Southwestern Indian of the Sinai Peninsula and . From 1000 I LAP A 2 • Fire Agate --, , ! . I AD. ; .• J \ GIL A ! i .. -1' ~ i turquoise jewelry is crafted by Indians both to the early 1800's, Persia (Iran) produced I • ",,.,., working individually and in production fac­ the majority of the world's quality material. .1 11 FI RIC a P A "' • Tur~ise .I.. " ~ i .,' r---, ,_ .. _...... ' •• - ..J I tories. After 1800 Western Hemisphere deposits I • ----.. _., Jasper • Agate p Clot • 'j i ! r'. Apache Tears \. er~ T~ise Z t produced the gem for worldwide distribution. I: I : _ .. _...... ~ cOClDeF"Minerals Copper Minerals .... -,--.• -1 ,'.I . \. I Mineral rights to gemstone deposits on Federal Within the past twenty years, the southwestern \ V" I.LI i Lands are acquired under the location patent United States has become the source of a major ) YUMA PINAL CRAHAM\a.:! / ,~I system of the General Mining Law. One quantity of the world's material. /-. • Fir e Ag iH e ~ , '. • 1 1 notable exception is petrified wood which is j .. _ .. _ .. _ .. _ .. _:-.. - .. - .. ~ :\ ~ ...... , Petrified Wood L ___ .. _____ .. ,_.. _ .. _ .._ •• _ .. _ • .-. specifically excluded from the mining law. Turquoise was traditionally set in as yel­ ~- ...... Copper Minerals low gold formed a distinctive background for ...... , ...... • Aquamarine the light blue, traditional Persian stones. These '-" ·...... ·l: P I M A TURQUOISE stones originally considered the standard of , ...... comparison, are often so pale that they are not ,.,...... cae HIS E Turquoise ranks first in value of the State's wanted by modem workers in silver. The deep ...... Opa l .---t"'""---·i Petrified Wood ...... : . gemstone production. Turquoise is a sky blue blue and green stones, typical of the Southwest, LOCATIONS OF SELECTED GEMSTONE ...... _ ..ls ANT AI . .Turquoandise ...... I , Jasper to greenish-gray hydrous phosphate of are most effective when set in silver. PRODUCTION IN ARIZONA. " ...... ~_._~._'-_.i_. __ ._____ . __ . .:~:~~rals aluminum and copper. In the last decade it ..C"". Olin: MIl .....c •• MIl. lila.. became so popular that it was instrumental in

2 GEMSTONE PRODUCTION IN ARIZONA

by Ken A. Phillips, Chief Engineer

Text of a presentation made before the Arizona Industrial Mineral program of the 117th Annual Meeting of the American Institute of Mining, Metallurgical and Petroleum Engineers , January 25 - 28,1988 ABSTRACT for most of the value with amethyst, chrysocol­ la, azurite, malachite, fire agate, Apache tears, Arizona leads all other states in the value of and gem smithsonite making up all but a small gemstones mined with an annual production amount of the remainder. These data do not that exceeds $3,000,000. Gemstones are an include the large amount of gem material col­ important component of the mineral wealth of lected and consumed, traded or resold by the the State. Turquoise, peridot, chrysocolla, rockbound-hobbyist. The official number on petrified wood, fire agate, and crystallized status for Arizona may change or have already mineral specimens are among the gemstones changed because of the high value of fresh commercially mined. Numerous additional water production in Tennessee. Al­ deposits are operated by hobbyists. The State's though technically produced by aquaculture reputation as a source of gemstones and and not mined, are classified by the U.S. specimens for the collector and adds Bureau as gemstones and their value is included to the economy of the State by attracting in official totals. tourists. Production of gemstones further adds to the State's economy through employment in It is likely that rockbounds collect as much or the value added gemstone processing industries more than the $3 million in official production. and by employment of Native American It would only take 3,000 rockbounds to collect craftsmen. 1,()()() pounds of material each worth only $1.00 per pound to exceed the reported production. Although much of the rockbound production GEMSTONE PRODUC1l0N IN does not enter commerce directly, the rock­ ARIZONA hound-lapidary-mineral collecting hobbies do have a multimillion dollar impact on Arizona's Arizona ranks number one in the value of retail trade and hospitality industries. For ex­ gemstone mining in the United States. ample a single gem and mineral event known Approximately $3 million worth of commer­ as the Quartzsite Pow Wow held in February cial gemstone production was reported for typically draws over 250,000 participants while Arizona by the U.S. Bureau of Mines in 1986. the Tuscon Gem and Mineral show draws Turquoise, peridot and petrified wood account dealers and exhibitors from throughout the