<<

AP42 Section: 11.22 Reference: 2

Title: F. L. Kadey, "Diatomite", Industrial Rocks And Minerals, Volume I, Society Of Mining Engineers, New York, 1983. 1976, "The :ameters On mond Bits .. . PP. 82-89. Diatomite use Of.Dio. . P: 166. "Abundance FREDERIC L. KADEY. JR.* 21. 157, No. des of Dia. ha (Johan. 5-9. nd AppIita. .ME Preprint ' York, 8 pp, oesticide extender to name a few representative esis." Indar. Diatomite is a siliceous, -199. consisting principally of the fossilized skeletal applications. . 1961, "The remains of the , a unicellular aquatic The United States is the principal producing AsIrouhysics plant related lo the . Thus, it has been country, although diatomite'is foind In numer- ous other locations. ~ formed by the induration of diatomaceous ooze, 5 Mechanical - and consists mainly of diatomaceous silica, a I Diamonds," .. form or variety of which is first formed Geology in the cell walls of the living diatom. Dia- he Diomond, j tomaceous silica is not generally regarded as a Composition and Morphology ' synonym ' or the equivalent for diatomite, although it has been so used at various times. Diatomaceous silica qualifies as a mineral Of Accurately, diatomaceous silica is the preferred organic origin in much the same way that name for the principal mineral component of. aragonite and collophane do. The silica of the which the rock, diatomite, is composed. The fossilized diatom skeleton closely resembles terms diatomaceous earth and kieselguhr are opal or hydrous silica in composition used as synonymous with diatomite. The desig- (SiO;nH,O).". The silica is of acute nations tripoli, tripolite, infusorial earth, etc., biological significance, not only for the cell wall _. were used at one time but are now obsolete. component, but also for the hasic life pro- With the changing nomenclature, these terms cess.16. Without silica, cell development that were at one time correct when proposed ceases."' In addition to bound water, varying and used for generations would he considered between 3.5 and 8%, the siliceous skeleton may incorrect if used today in the light of current also contain, in solid solution, or as part of the knowledge. The designation diatomite is re- SiO, complex, small amounts of associated in- ' served for those accumulations of diatoma- organic components-alumina, principally- ceous silica that are of sufficient quality, size, and lesser amounts of iron,'c, m alkaline I and minability to be considered of potential earths, alkali metals, and other minor consti- 7 commercial value. tuents."g. 6i Boron is reported to be an essen- :' Processed diatomite possesses an unusual tial element for diatom growth.", Since j particulate structure and chemical stability that diatomaceous silica is not pure hydrous silica lends itself to applications not filled by any hut contains other intimately associated ele- other form of silica. Foremost among these ments, there is good reason to consider it a applications is its use"as a filter aid, which distinct type or variety.' Associated with the accounts for over half of its current consump- diatomaceous silica, and integrated as part of tion. Its unique diatom structure, low bulk the diatomite, may he variable amounts of organic matter, soluble salts, and particles of density, high absorptive capacity, high surface rock-forming minerals that were syngenetically area, and relatively low abrasion are attributes deposited or precipitated with the diatom frus- responsible for its utility as a functional filler tules. Sand, clay, carbonate, and and as an extender in , paper, rubber, and are typical common contaminants. Other con- in plastics; and as an anti-caking agent; thermal taminating minerals may be present, such as insulating material; catalyst carrier; and chro- feldspar, , amphiboles, pyroxenes, rutile, matographic support; polish, , and zircon-the result of weathering, then trans- -. porting, and subsequent redeposition of sur- - * Exploration Manager. Manville International rounding land masses, Commercial diatomite Corp.. Denver, CO. may also contain fragments and particles of 678 Industrial Minerals and Rocks .. other such organisms as silico-flagellates, radio- consistent and orderly design (Figs. 1-3). laria and siliceous sponges, Furthermore, each valve appears to consist of In a commercial diatomite. silica makes up an inner and an outer platelike surface, sepa- the bulk of the chemical composition: usually rated by ribs that result in a chambered inte- over 86% and as high as 94%. Alumina and rior. The structure of each surface is different iron generally are at least 1.5 and 0.2%. re- in that the nature of the openings from each spectively. This includes not only that believed surface into the chamber is not necessarily the to be incorporated as part of the skeleton but same. It is on the basis of the' valve structure iron and alumina associated with many of the that are classified. The openings in the . ' contaminants. Lesser amounts of other ele- skeleton, classified by diatomists and divided ments, a small part of which may be secreted into primary, secondary, and in some species, in the diatom skeleton, comprise the balance structures, are believed to simply sup:.& of the total chemical composition. The manner port the membrane of the living diatom through ,,

in which many of these elements are associated which the nutrients pass by the process of os- .#- !

is not presently known. Table 1 illustrates the mosis. The valves vary between approximately jr e chemical composition of diatomites from vari- 5 and IOOOp in diameter, or maximum dimen-, ' ous areas.' Although diatoms appear amor- sion, depending on the genus (Fig. 4). Most . phous under the light microscope, X-ray studies species fall within the range of 50 to lSOp, Itl show untreated diatomite to have a broad halo is not within the scope of this chapter to dwell in the region of the principal cristobalite peak, further on the botanical aspects of the diatom, thus it has been referred to as "micro- although a few of the numerous references on amorphous." & The main X-ray line is an ap- the subject are included in the bibliography for proximation and not identical with a-cristo- the interested reader. . , .. balite.6G Some researchers have reported Suffice it to say that outside the realm of 8-cristobalite to be prevalent." The crystalline mining and commerce, the diatom has its own impurities produce their own X-ray lines; hence nomenclature and scientific entity, the study of they furnish an identification of their nature, to which distinguishes it as a source of enjoyment a greater or lesser degree, depending on the for amateur and professional microscopists amounts present. The ultimate hardness of the alike: and as a scientific tool in the fields of diatom skeleton is between 4'h and 5 on the limnology, stratigraphic correlation, and other Mohs' scale. After calcination or flux calcina- similar noncommercial applications.3. 7s. 82, 85* . tion. the Mohs' hardness is increased to 5% to 'N Certain properties of diatomite-physical . . 6. The friability, or the propensity of the and chemical-may be visualized as primary or ' . . skeleton to break down, rather than to abrade, fundamental in nature. The nature and con- renders a measurement of hardness meaningless figuration of the skeletal structure, specific without also a consideration of the particle gravity, refractive index, hardness and fri- '. size."* The specific gravity ranges from 1.95 ability, and composition are a few. These are. . to 2.3. In calculating settling velocities, bulking the properties that determine secondary or de- values, etc., an apparent specific gravity of 2.0 rived properties which also endow diatomite for natural milled powders and of 2.3 for flux with the attributes that set it apart from other calcined powders is generally used.'J' Refrac- sources of silica. It is an accurate generaliza- tive index is variable between about 1.40 and tion to state that the skeletal structure or con- ' . 1.46 for natural earth, and increases to 1.49 figuration of the diatom is the principal primary for flux calcined diatomite. property that controls most of the derived or Taxonomically, diatoms are divided into two secondary properties. Low bulk density, low . broad categories: Centricae (discoid) and Pen- wet or cake density, and high surface area may natae (elongate to filiform). The study of the be visualized as examples of derived or sec- various intricate shapes and structural patterns ondary properties. The loose weight and wet of individual siliceous skeletons is as old as the density, for example, are a function of, and use of the light microscope itself. Each form depend on, the skeletal Structure and specific consists of two valves that are bound together gravity. The and shape on which by a connecting band or girdle. In the living bulk and wet cake density depend can be altered diatom, these encase the cell contents. to a degree by milling: but ultimately, they are Each siliceous valve is punctated by a system determined by such primary propertiff as strnc- - or pattern of openings that are arranged in a ture, density, and friability. Certain properties - h

Diatomite 679

. 1-3). 3(oLnOOO~(oO* Insist of lL?Yl7NTqYlO)II)? O--000P00~ :e, sepa. r 'ed inte. different im each lrily the tructure rs in the divided: species, PIY sup- through s of os- cimately dirnen. 8. Most so,. It 10 dwell diatom, nces on .phy for :ah of its own tudy of oyment scopists elds of- d other 5. B?. *5, physical nary or .d con- specific id fri- ese are or de- itomite L other :raliza- c con- rimary red or

f3 . low a may 'r sec- d wet i, and pecific which :Itered 3y are struc- wties

Diatomite 681

... b

.A. 9 as pH, water solubility, and abrasiveness can chemical balance of silica in marine and in be modified by extraneous material that was lacustrine waters is scientifically rec~gnnized.~~~ deposited syngenelically with the diatoms. Si. 48, 08. 00 ? Environmental conditions for groa-th include at least the five following major requirements: i Mode of Occurrence and Origin ~ i: The or siliceous skeleton of the 1) Large shallow basins (preferrably 35 m or i! diatom, a unicellular or noncellular microscopic less in depth) for deposition, so that photoswhesis r. algae, of the class Bacillariophyceae, and the can occur. With regard to lacustrine deporiis, a - order Bacillariaes, serves as the ultimate build- shallow provides sufficient actini; lisht for ing block of which diatomite is composed. The photosynthesis for not only pelagic diatoms. but group comprises over 300 genera and 12,000 to also for benthonic forms attached Io siones and to plants on the lake bottom. In the cze oi thick , 16,000 species. In living form, accumulations deposits of marine diatomites, there is evid:r.:c tor of the diatom may-be seen as the iridescent a down warping of the basin of delvjiiioc. lhus scum on ponds, the slippery gelatinous film on maintaining fairly shallow water fo: kn5onii seaweed, on the bellies of certain species of species. The open sea is reportedly L?c ksl en- whales, and other such varied habitats as vironment for pelagic diatoms. oceanic ice floes, hot springs, moist soil, and 2) An abundant supply of rolub!c sil- particularly as masses of planktonic colonies on ica,n. S. 31, '3, 51 There is B worldwid- corre!ation b the open sea. Their natural function appears to between the erirtence of thick diatomlrc de;asits be that of a food for other organisms of the sea. and proximity to volcanic ash ~:urrcr;es.". A. Furthermore, thek role in controlling the geo- While volcanic ash does not necesssriiy hzve to 682 Industrial Minerals and Rocks accompany dintom deposition, some mechanism than 1 mm per 1000 years for deep sea red pected that a for increasing the silica content in marine and clay, to I cm per 1000 years for calcareous- ” fication deals lacustrine bodies beyond the present day norm is ‘nearer the continent.5’. 80 In of freshwater necessary for the formation of commercially thick comparison, the rhythmic banding seen in Lom- added to thc deposits. There are numerous examples wherein whether deFo marine and nonmarine deposits meet this condi- poc, CA diatomites suggests a rate considec- or bog origir tion. Typical of these are at Lake Myvatn, Iceland; ably faster than that-probably of the. order of in the state of Jalisco, Mexico, where the deposits I mm or more per year. Gross has calculated because the di border the ancien1 shores of Lake Atotanilco; and a rate of 4 mm per year for a marine envirc those occurrences bordering Lake Rotorura. New 25% diatom-75% silt , deposited in those that livr Zealand: in Nevada the late Virgin Valley Sannich Inlet, B.C.‘osi ’ .\‘9 association of beds in Humbolt County, and the early Pliocene After deposition, such subsequent geologic as seen by m Esmeralda formation in Nye and Esmeralda Coun- forces as consolidation, burial under what will . serves to diffe ties: the Payette formation in Idaho and Eastern later be overburden, regional uplift, and par- water, but all . These all are associated with volcanism. - tial erosion come into play to expose, yet pro-. L deposit locatit Deposits of marine diatomite exhibit a similar correlation: the late Miocene-early Pliocene Sisquoc tect, the deposit for later discovery .and .-‘L ple may havr semblages, lil formation which comprises the Lompoc, CA exploitation. ,, r ~ ’2 7 :,, 7 diatomite; the middle and late Miocene Monterey Because of the delicate nature of the diatom . dividual loca formation of the Ranges; and the middle skeleton, deposits of diatomite to be useful to differences rei Miocene Tremblor formation east of Coalinga, industry cannot underno any meat degree of out, diatomit< CA, are examples of diatomites associated with regional metamorphism or chemical alteration. produce a ri contemporary volcanism. Particles of volcanic ash For this reason, geologic conditions that have. uses to whic are a common contaminant of some diatomites. merically, mc 3) An abundant supply of nutrients. In most not resulted in an appreciable degree of con- world are of that are nontoxic to diatom proliferation the solidation or of cementation are preferable. supply of nutrients is often more available than is When orogenic forces are excessive, the result- ever, those o the supply of silica. ing metamorphosis produces opaline . merous, tend 4) The absence of toxic or growth-inhibiting porcelanites, and similar more indurated ma- constituents in the water. Although few lakes terials of noncommercial interest. contain toxic water in the usual sense, many in In place, diatomite is soft and “punky,” and which the rate of evaporation exceeds inflow dur- has a chalklike appearance. Color may vary ing long periods of the year build up concentra- from snow white in a pure, well bleached and tions of soluble salts to the point of inhibiting dry deposit, to olive green or darker where sub- diatom growth.“, ‘”, le, 5) A minimum supply of clastic sedimentary stantial organic remains are still present and materials. While this, per se, is not a requirement where moisture content is high. It may exhibit for diatom growth, low nondiatomaceous con- stratification, caused by either, or both, sedi- tamination is paramount for the development of a mentation of particularly flat beds or a pre- commercially suitable deposit. ponderance of discoid diatoms, or by seasonally rhythmic deposition of clav and other immri- The effect of temperature, light, pressure, and ties. On the-other hand, it may be’massiveand’; other factors on diatom growth has been dis- show no stratification. It may be so loosely‘ I cussed.”. M. 61. 185. 20*. 2DB In addition to its consolidated that when handled, a field sample unique siliceous skeleton, the living form has will readily break down to a powder, or it may , FIG. 5-Mia a nucleus, it produces certain protoplasmic be hard enough to crack “brittley” when struck marine dial substances by the process of photosynthesis, with a hammer. In addition to induration blage from and incidental to its metabolism, it manufac- through consolidation, precipitation of car- CA. tures oil and vitamins. The rate of reproduc- bonate for example, or “baking” by volcanic ’ . tion of diatoms varies with the species from flows can destroy an otherwise good deposit.. between two or three times a day to once a The better quality diatomite is lightweight, week; and one diatom may have 100 million usually possessing a block density between 20 descendents in 30 days.’8s. ?O0. :os Deposition and 34 Ib per cu ft. ..j.! of the skeletal remains occurs after it has served I its natural function. Thus, given the right con- Classification of Deposits I ’ ditions of environment and geologic location, tremendously thick deposits of diatomaceous The various species of diatom thrive in either ooze may build up on the floor of the containing a marine or a lacustrine environment. Some body of water. forms live in brackish waters. Identification Of -- Potassium-argon dating of volcanic minerals the diatoms from an unknown deposit label it and glass in North Pacific has estab- as having been laid down in either one environ- lished Tertiary sedinlentation rates of from less ment or the other. It is, therefore, to be ex-

-- . I *’

Diatomite 683 eP sea red pected that a major criterion of deposit classi- Distribution of Deposits :alcareous. fication deals with whether it is of marine or It.% 80 In of freshwater origin. Some investigators have The occurrence of diatomaceous silica is m in Lom. added to the environments just mentioned, widespread throughout the world. Although .I Consider. whether deposits are of modern lake, marsh, algae appeared quite early in geologic history, :le order of or bog origin.$ These criteria are important commercial deposils are generally restricted to calculated because the diatom assemblages associated with sedimentary formations of Tertiary and of later year for a marine environments are quite different from age, and further limited ecologically by those :posited in those that live only in freshwater habitats. The conditions for formation that have been previ- .~. ~ association of forms or the diatom assemblage, ously described. However, when one considers it geologic as seen by means of the microscope, not only the numerous other limiting factors that must - what will serves to differentiate marine origin from fresh- be taken into account before an occurrence . and par. water, but also in many cases, to identify the qualifies as a commercial deposit-quality. e, yet pro. deposit location from which an unknown sam- rninability, location, and size-then the num- *very and ple may have come (Figs. 5-9). Diatom as- bers are few indeed. While a good portion of semblages, like fingerprints, are specific to in- the coast could be considered “diato- the diatom dividual locations. Because of the structural maceous in character,” an area of hardly more : useful to differences related lo origin, as has been pointed than four square miles contains diatomite of degree of out, diatomites have a range of properties and high quality, commercial value. alteration. produce a range of effects in the numerous . uses to which they have been applied. Nu- that have North America :e of con- merically, most of the known deposits in the ,referable. world are of lacustrine origin. Generally how- United States: Occurrences of diatomite have the result- .- ever, those of marine origin, although less nu- been reported from just about all of the east le cherts, merous, tend to be larger. and the west coastal states, and indeed, from rated ma- . nky,” and may vary iched aEd- *here sub- esent and ay exhibit 0th. sedi- a pre- easonally r impuri- ssive and 3 loosely d sample 11 it may FIG. 5-Micrograph ot enstruck marine diafom assem- iduration blage from Lompoc. of car- CA. , volcanic - deposit. itweight, ween 20

in either t. Some :ation of t label it environ- o be ex- 684 Industrial Minerals and Rocks

FIG. 7-ML FIG. &.Uicropaph of bog diatom lacusrrinr dimom a- sembloge from Carlin, from PG Bra NV.

.- 100 p '.a, . , ;,: :, posit is now 1 .* many bordering these states in the interior of ft thick and is pan of a thicker diatomite series .'", . of commerc the country. Commercial production, however, of marine origin belonging to the Sisquoc for- County has ' ha5 been limited IO a few of these. First Ameri- mation of late Miocene or possibly early Plio- are other I Second to C can production war from , where cene age. Although the Lompoc diatomite may , ' from 1881 until 1930. marine diatomite was have been known since the time of the Spanish ,'.' where diatc extracted from the Fairhaven member of the Conquistadors in the 1760s, it was not recog- mined in tv middle hlicxene Calven formation.'2a, n5 This nized as such until over a century later, and first : Cyprus Iodi diatomite outcrops along the banks of the Pa- mining was not started until about 1890.? The. Minerals D: tuxent, Rappahannock, and Potomac rivers; strata at Lompoc, which present a good exam- mine diatoi and in cliffs along Chesapeake Bay. It is con- ple of rhythmic bedding, are mined by the and at Clai taminated u%h varying amounts of loosely held tration and Minerals Div. of Manville Interna- .. Tertiary or .-- silica sand. most of which can be removed :in tional Corp. principally from a broad pitching are close to processing. More intimately held montmoril- syncline with related smaller anticlines and syn- -.'- in.moisture lonite, illite. and kaolinite are also present. clines. Quarries located at strategic places on Dicalite Di Removal of the clay on an experimental basis the flanks and nose of the major syncline, and deposit neai has been attempied with little practical success, related structures, permit extraction of crude pah in soul for other than low quality applications."!' To- from various parts of the stratigraphic column, day, the remains of a diatomite enterprise of thus allowing for blending of crude types lo fit lacustrine d bygone years can be seen at such places as the product demand. The Dicalite Div. of Div. of Wii Kaylors Landin!. MD, lying idly and in ruins. Grefco, Inc. also produces from an area in the there was p: The largest and most uniform deposits in the general Lompoc district. / WA. Minbi world are to be iound in the vicinity of Lompoc, Diatomite was mined by the Dicalite CO. - Oregon 'Ii CA (Fig. IO). The diatomite sequence of from a deposit in the Palos Verdes Hills near that have pr commercial significance is of the order of IO00 LOs Angeles starting in the 1930s, but that de- Idaho and

. Diatomite 685

..

I. :e& 1q &,&

$; ", FIG. 7-Micrograph of bog diafom assemblage from Pernambuco, Brazil.

wI, p ?" -.

100 p posit is now depleted."'0 A massive embayment freshwater diatomite in western Kansas was .te series of commercial freshwater diatomite io Shasta mined by the Delore Div. of NL Industries uoc for- County has been outlined by Grefco, Inc. There until 1977. Florida has bog and lake bottom rly Plio- are other minor operations in California.220 deposits near Pensacola and in central Florida lite may Second to California in production is Nevada, that have received exploratory attention in the Spanish where diatomite from freshwater deposits is past. Noncommercial bog and lake deposits are t recog- mined in two principal areas. In addition to well known in Maine, New Hampshire, Massa- and first Cyprus Industrial Minerals Co., the Fibers and chusetts, and New York. Some of these were 0.2 The Minerals Div. of Eagle-Picher Industries, Inc. operated on a small scale in earlier years. 3 exam- mine diatomite from deposits near Lovelock Canada: Production in Canada at present is the Fil- and at Clark, near Reno. These are of late limited to freshwater Miocene deposits near Interna- Tertiary or Pleistocene age. The beds at Clark Quesnel, B.C., where Crownite Diatoms Ltd. >itching are close to the surface and are relatively low and Pacific Diatomite Ltd. produce a fertilizer .nd syn- in moisture. Diatomite is also mined by the grade product. Eastern Canada has well-known aces on Dicalite Div. of Grefco from a freshwater occurrences in Nova Scotia and New Bruns- ne, and deposit near Basalt, about 60 miles from Tono- wick that are not profitable to exploit at the i crude pah in southwestern Nevada. In the state of present time. :olumn, Washington, diatomite is produced from a Mexico: Diatomite occurs in several states 3s to fit lacustrine deposit near Quincy by the Kenite in Mexico, and among these are Tlaxcala, 3iv. of Div. of Witco Chemicals Corp.' At one time, Colima, Jalisco, Michoacan, and Mexico. Some I in the there was production from a deposit at Kittitas, production has been known since 1927. Good WA. Minor production has been reported from quality earth is mined near Catarina in Jalisco ite Co. Oregon 'lo and from Arizona."e Other states (Fig. I I) by Diatomita San Nicolas, SA. de Is near that have produced diatomite in the past include C.V. Filter aids and fillers from this operation hat de- Idaho and Utah. A mixture of carbonate and are shipped to Latin America, Europe, and Aus- Industrial Minerals and Rocks

., ,.. . _. . . --- .I. _---. FIG. 8-Micrograph of' FIG.9-Micr lacustrine diatom m- -~ modern lake < semblage from Elchc '-, semblage fro1 de la Sierra, Spain. Icela! .... - i ' ,. ,. .

lm)L tralia. @.her mmmercial deposits are exploited mann Mineraria S.p.A. at Castel del Piano, all at Zacqu a03 at Tuxpan by Kieselguhr de near Monte Amiata. Diatomiti Italianc A.P.E.S.- calcining. n. Zfcuco in Mkboacan. Production has been S.p.A. operate further south in the Viterbo been known re?& 31 Xlcgdalena and Cocula in Jalixo.* area, and Diatom S.p.A. mine a deposit at. is mined by ax La Bxing h Tlaxcala, at San Xlartin Tex- Castiglione in Teverina. Medium grade diato- lake basin dt melucan in Pcebla, and at Ixtlahuaca in the mite is mined in the area of Tombolia in north- . land, U.K. .- State of Mexico. ern Italy. Good quality Spanish diatomite is not suitable mined from lacustrine deposits between Hellin usedinostly f Europe and Elche de la Sierra by Manville Espaeola An unusua The 3cm significant European sources of S.A. in the southeastern part of the country. is the diatom- diatmiv -e freshwater Tertiary and Quatcr- Some of these deposits were mined from under- Moler. This nap ds-mirs lirated in the Massif Central area ground galleries for over 50 years, but in recent because of ti oi wumFcnce. Deposits at Collandres, and years have been converted to open pit op- -' over 200,OC at Sainl-kuz?:r (Ardeche) in the Privas area, erations. Some of the earth is a remarkably elsewhere in are ~orkhib! Soc. CECA (Carbonisation et white color, but lenses and carbonate for insulatin Charborn .aces). A deposit near hlurat, mined beds necessitate highly selective mining meth- of Tertiary b>- ZlanviUs ck France, is processed into filter ods. There are other, low quality occurrences Fur and M( gds. Tze Lmeburzer-Heide deposits of West- in Spain, including a marine occurrence near atomite of E ern Gemmy &-erethe first commercially mined Almeria. In Iceland, a diatomaceous ooze of recent years deposits in rh world, but have declined in Holocene Age is dredged from Lake Myvatn There are hpomcr in recent yep Some production and pumped in slurry to the processing plant by Although li is. is. ban-er. rqorted from Tagebau and from Kisilidjan, H.F., where the volcanic ash is re- ..- duction is Lntsrlujs by Kieselguhr Industrie GmbH. In moved by hydroclones. The resulting slurry, - 300,000 tp! Italy. cc.nmerSa1 deposits are located at Arci- after pumping to settling ponds, is dewatered exist near 1 dmad Sacra Fiora and mined by Winkel- and dried with geothermal steam prior to flux Anatolia, TL 687

raph 01 Im as Elchr ipain.

no, all P.E.S.. Jiterbo osit at diato- north- nile is Hellin paiiola iuntry. under- recent lit op- rkably bonate meth- rences e near oze of Iyvatn by is re- slurry. atered 0 flux 688 Industrial Minerals and Rocks

ince. Ther' Brazil. The the most de are reportec rences. Per Chiclayo, ar of high brigi Colombia, ( tioquia. Di: other Latin

Asia There is ment of der growing inc lacustrine d cal Co. D markets, exi has comme known. 'I? Australia ai quality, tht principally increasing lending me FIG. IO-Aerial view showing extent of Manville diatomite quarries ar Lompoc,CA. sible develc .. bog deposi portion of the production is shipped to France and Gerald South America ..I and Italy. There is a marked similarity in ap- Elsewhe: pearance between the Algerian and Lompoc Production of the order of several thousand occurrence diatomites when viewed under the microscope. tons per year is mined from small, scattered ,.~. one reason The diatomite from however, is charac- deposits in Rio Negro Province in Argentina.,?, ; Furthermo terized by a noticeable amount of carbonate Much of the earth occurs under a basalt cap, :;: = ooze are fc contamination, and is deficient in many of the which necessitates mining from galleries and inz,,.-!, deposits of diatom types that, in the Lompoc earth, provide one instance as an open pit operation after. '. a better balance for . Numerous, in- blasting away the basalt. There are also small; " Reserves tensely folded, thin beds occur near Moste- impure occurrences in San Juan province ne%,.,'-. ganum, Algeria. Calingasta, and in remote parts of Salta Prov;:, Present .. . ,. beyond th, ',., . .,.; 7. :$*2&. posits are ...... , . tion throu velopment grade CN~ considere( ability, or new imp begin to

Keepin limiting c diatomite suitable t' easily ero or in roac One w Diatomite ince. There are numerous bog deposits in ing would be fruitful in the search for diatomite Brazil. The states of Ceari and Bahii contain horizons in conjunction with higher density the most deposits, although eight other states beds. So far, however, no successful operations are reported to have smaller impure occur- of this kind have been reported. Geophysical rences. Peru has occurrences at Pisco. Piuri, refraction seismic surveys have successfully Chiclayo, and Arequipa; and Chile has deposits outlined the depth of shallow fresh water diato- of high brightness earth at Arica and Chiloe. In mite basins. This works particularly well where Colombia, diatomite occurs at Tunja and An- the soft (low velocity) diatomite is underlain tioquia. Diatomite occurs to a lesser degree in by higher velocity basalt (C.M. Smith, Grefco, other Latin American countries. Inc., personal communication). Geochemical methods so far have not been adapted to the prospecting for, nor exploration of, diatomite. However, narrow pass-band There is considerable potential for develop. infrared imagery (34 and 4,5-5,5 Inen‘ Of deposits in the Far East’ japan has a ters) has been used to recognize diatomite from growing industry based on its own marine and aircraft by its thermal characteristics.i” Changes lacustrine deposits operated by Shows Chemi- in vegetation have been noted Over diatomite- cal Co. Deposits, possibly suitable for local hearing of bog deposits, and this might markets, exist in Indonesia and in Korea. China indicate the possible application of has commercial deposits about which little is techniques in prospecting, known. There are several small deposits in Australia and in New Zealand, hut for filter aid When carried to the point of development, quality, these depend on imports, exploration of diatomite deposits is pursued in principally from the The pressure from stages. After an occurrence has been recognized US. through prospecting. usuaW, the first step in increasing transportation however, is exploration consists of a preliminary sampling lending motivation to the exploration and pos- sible development of shallow mediocre quality of all visible outcrops. The nature of the ma- CA. terial is noted and recorded by measuring the . bog deposits in Western Australia near Perth attitude of the beds, and by observing all other and Geraldton.228 Elsewhere in the world are other visible structural and stratigraphic features. of diatomaceous silica which, for Sampling intervals are divided into visible in- , thousand crements if bedding, textural, and color changes scattered one or another, have not been exploited, Furthermore, accumulations of diatomaceous or stratification are evident. If thick enough Argentina. and no visible divisions are apparent, the strati- Jasalt cap, are forming today that will the. deposits of “tomorrow.” graphic interval spanned by each sample should ries and in he no more than 150 cm for each channel cut. ition after In this way, nonvisible characteristics-diatom also small assemblage, chemical changes, etc.-may be vince near noticed and characterized during testing of the Present reserves are estimated to be adequate ;aka Prov: samples. In subsequent exploration stages, the Presently known de- beyond the year 2ooo’ 150.cm internal may he reduced, if required. posits are stretching beyond forecasted deple- Evidence of staining, degree of consolidation, tion through thP’efforts of research and de- judgment of color, bedding, and stratification, velopment in finding methods to process lower .etc,, are all field characteristics that are im. grade crude. Other deposits that are currently portant, and which should he noted. Pending considered marginal by virtue of quality. min- favorable results from the laboratory evalua- ability, or accessibility will undoubtedly take on tion of the samples, the next stage of explora- new importance should the present reserves tion is planned to delineate the reserves within iew begin dwindle. of one to the area and to further assess the quality. With omira San horizontal beds under relatively thin over- rarries at burden and in areas of gently rolling topogra- ‘isco, Mex- phy, the digging or augering of vertical explora- I. Keeping in mind the previously described tory shafts to expose the entire stratigraphic limiting criteria for formation, prospecting for column has proven highly satisfactory. In diatomite entails reconnaisance of potentially countries with low labor rates and in locations suitable terrain. Because it is usually soft and where mechanical equipment is difficult to easily eroded, white “showings” in stream banks maintain, hand-dug shafts up to 50 m in depth or in road cuts should he investigated. have many advantages. When these are of the One would surmise that gravimetric survey- order of I to 11% m in diam, ingenious “bird 690 Industrial Minerals and Rocks cage" types of sampling platforms. lowered by suitable for dry deposits, specialized techniques of high S windlass into the hole from a tripod arrange- must be developed for bog deposits and for- sign of a s ment. have been used to support a geologist, those occurring under lakes or ponds. is an attr only after who logs the hole and collects samples from the In the case of shallow lakes, sample locations been axel wall of the shaft. Whether hand-dug or are marked with survey poles driven into the sured in t machine-bored with a large auger, these open- ooze. Peat bog samplers that extract a 30 to ings in the deposit have the advantage that the the perfor 60-cm incremental sample have been designed specific, c structure and nature the beds may be noted of with long shafts so that a sample can be ex- The millin and correlated from hole to hole. Where over- tracted from as much as 8 m helow the surface.' of course. burden is minimal or nonexistent, holes dug by These may be used from a boat or raft that is . receive in backhoe have been used. While these have the floated into position and anchored. Some pre- - microscop advantage of the speed of excavation that is ' liminary field testing can be incorporated.i?to . sity, screei provided by mechanical equipment, depth is the exploratory phase of deposit ev?luation. . , sorption. f limited to about 6 or 7 m at the most, Field examination samples by portable of mi-%* '. resistivity. Core drilling in diatomite is specialized and croscope can reveal considerable information..:-. :acid solub requires special equipment and experienced Other obvious field aids include an HCI for,:.,' ., content a: drilling crews. Little, if any, good quality carbonate, a grit test by grinding the crude be-,;_ many cha: diatomite will produce satisfactory core with tween teeth, and the noting of appreciable water3; . . various ai a diameter of less than 10 to 15 cm. Any for- solubles by taste, .. ated io I mations that will, are usually too highly con- generate t solidated to be of much commercial value. A Evaluation of Deposits special ar IO-cm core if possible to obtain, however, pro- '.$' 3% methods. vides the amount of material that is required A preliminary idea of quality can be gained for testing. Where any amount of topographic from the foregoing field observations. The most relief is present, trenching by bulldozer on hill- obvious recognizable property is color. The sides will expose the bedding and will permit higher the brightness of a diatomite, the more Mining subsequent channel sampling, The opening of attractive its potential as a filler is likely to be. trenches by bulldozer across the bedding of Another property that is evident in the field is By and dipping strata will remove overburden and block density. A low block density is indicative, deed the expose the strata for sampling. among other things, of freedom from contami- United St The positioning of drill holes, shafts, or nating solids, such as sand and clay. Diatom In Europ trenches to adequately cover a deposit, depends type and degree of consolidation are also re-' .:/ of Asia. c upon a number of factors. Sample positions are flected in block density. A low degree of con- . . ground as most commonly arranged systematically in a solidation is desirable. Highly consolidated di-: . -- Myvatn is grid to cover the area to be explored. The dis. atomites are difficult to mill and result in ' water anc lance between sample locations is dependent, degradation of the skeletal structures. As previ- ~ essing pla among other things, on the lateral variation in ously mentioned, the most useful tool in the In the I important properties or characteristics of the field is a portable microscope. When performed. United Si diatomite. Where important properties are by an experienced operator, microscopic ex- Since bla: thought or known to change rapidly with lateral amination in the field can be used to ascertain bulldozerr extent. holes must be placed more closely to- diatom constitution and contaminants, to di- required ! gether than when a high degree of uniformity rect the course of exploration, to provide a the mill. is experienced in preliminary study. (Sample stratigraphic correlation, and to eliminate the at Lomj holes, on as close as 30-m centers, have been shipping of useless samples to the testing center. __ loosen thL used.) While much useful information can be cob - into dies The advantage of two and three-stage ex- lected in the field, and can lead at that point to Euclid b ploratory programs is that exploration can be- a firm recommendation by the geologist to nor shovels, : gin with a relatively economically wide spacing consider the deposit further, the ultimate judg- is an endl of sampling locations. Upon testing of the sam- ment of quality, however, is formed from the quarries ! ples from such a stage, a judgment can be made results of usually extensive testing in the labora- vertical s whether, because of unfavorable findings, the tory. The chemical analysis of a diatomite, .. the proc, program should be aborted, or if a subsequent while useful to some extent, is not an effective transport. program is needed in which the hole spacing is criterion in predicting the performance for most - abe flexit reduced. Subsequent stages of exploIation con- applications. It is to be expected of course that . at the mil sist of additional specialized sampling and of the lower the percent of nonsilica components, In SIt the selection of bulk samples for plant scale the better-to be sure their absence is essential powered trials. Whereas the foregoing methods piles wh, are in many cases. However, simply the indication I. Diatomite 691

:hniques of high SiOz content alone is not a sufficient the trucks for transportation to the mill. Where and for sign of a suitable crude. Chemical purity, then, hcrd contaminants' or thin strata are encoun- is an attribute that becomes more important tered, power shovel application may he re- ocations only after other indications of suitability have quired. heen ascertained. The properties that are mea- Although some operations outside the United into the sured in the laboratory are designed to reflect States are carried on by large companies and a 30 IO the performance of the finished product in a use modern mining methods, diatomite mining jesigned specific, or similar grouping, of applications. in many parts of the world is still, for the most I be ex. The milling of the crude in the laboratory must, part, a small or family owned operation, often surface. of course, simulate the treatment that it would from underground tunnels and galleries. and of it that is receive in plant equipment. Such properties as pick and shovel and wheelbarrow magnitude. ,me pre- microscopic constitution, loose weight, wet den- Where the will allow, the ore is spread ited into sity, screen size, brightness, abrasion, water ab- on the ground or on drying platforms, and the aluation sorption, filtration flow rate and clarity, pH, and moisture reduced to less than 20%. Rotary ;able mi- resistivity, and in specialized cases, and dryers are often used rather than simultaneous mnation. .acid soluble iron, calcium, and trace elemental milling-drying processes. 'I test for content are just a representative few of the At the Manville Lompoc deposit, extensive :rude be- many characteristics that are of importance in sampling and testing precede the mining 5le water various applications and which must he evalu- operation for quality control. Selective mining ated in the laboratory. Special applications then consists of separating "critical horizons" , generate the need and the design of additional which are sent to waste. In many smaller de- special and often relatively expensive testing posits, such as are prevalent elsewhere in the methods. world, selective mining of narrow beds by hand ?e gained to separate chert lenses and carbonate inclu- The most sions is widely used. lor. The Preparation for Markets The attitude of the beds, their thickness, the the more Mining distribution of intercalated impure horizons, :ly to be.- and thickness of overburden all have a bearing le field is By and large, the most economical and in- on the method of mining that is best to use. xdicative. deed the only method of extraction used in the Underground mining of horizontal beds con- contami- United States is quarrying or open pit mining. sists simply of following each stratum as far Diatom Io Europe, Africa, South America, and parts into the deposit as is economical. Then re- ! also re- of Asia, commercial deposits are mined under- covery of part of the remaining approximate e of con- ground as well. In Iceland, the deposit at Lake .44% that is required to support the roof is !dated di- Myvatn is dredged from beneath about 1 m of removed on the way out, if the mine is ever result in water and pumped in slurry form to the proc- depleted to that extent. ' As previ- essing plant 2 km away. Underground mining of inclined beds be- 01 in the In the larger open pit quarries of the western comes increasingly difficult with increased dip. serformed United States, nearly all use power equipment. Depending on topography and on the arrange- zopic ex- Since blasting is not ordinarily required, only ment of galleries, exploitation may not be eco- ascertain bulldozers, front-end loaders, and trucks are nomically feasible for any appreciable distance. ts, to di- required to extract and transport the crude to Open pit quarrying is obviously preferable to xovide a . the mill. In the Manville Celita operations underground mining because of. lower mining iinate the at Lompoc, bulldozer-rooter combinations costs and greater rates of recovery. When the Ig center. loosen the consolidated strata which are loaded beds are dipping gently, open pit mining offers n be col- into diesel-powered bottom-dump trucks by cbnsiderable flexibility in that quarries can be t point to Euclid belt loaders, by diesel and electric located where beds of a particular quality out- ,ist to not shovels, and by front-end loaders. The result crop, thus allowing for blending of severd late judg- is an endless procession of conveyance from the crude types. Horizontal beds in rolling topog- from the quarries to strategically located stockpiles over raphy offer similar advantages. le labora- vertical storage shafts. These are connected to jiatomite, the proceising plant through an underground Milling and Processing I effective transportation system, which permits consider- : for most abe flexibility in the blending of various crudes Because of the high moisture content of the wrse that at the mill. crude and other processing losses, it is highly desirable to have the mill as near as possible to nponents, In smaller American operations, diesel- the mine. Under unusual conditions, however, i essential powered scrapers convey the earth to stock- Indication piles where front-end loaders are used to fill crude diatomite has been trucked considerable 692 industrial Minerals and Rocks

FIG. 12Schematic representation of the min- ing, transporting, processing, and packaging of Cdite dintomite powders. Reprinted by speciol permission from Chemical Engineering.

. , I,, .,,,.... . , ....*, -. distances to a plant. The Manville Lompoc of particle size is effected by the addition of a ,,.. plant, for example, is adjacent to the quarries, flux-usually soda ash-before the calcining whereas the Manville Espaiiola S.A. plant 31 step. The use of sodium chloride as a flux is .. Alicante, Spain, is situated over 100 miles still common outside the US, although in this 1 from the source of crude. country, its corrosive action is avoided. Such Since the particulate shape and structure of products are referred to as "flux calcined." i the diatom skeleton is the physical property 1 It should be pointed out that the term "cal- t that most distinctly sets diatomite apart from cination" is a misnomer when referring to the other forms of silica, and for which its unique- heat treatment of diatomite. The process is not, ness is most responsible, great care is taken in the correct technical sense, one .of calcina- during milling and processing to preserve this tion at all. Rather, it is the agglomeration of structure. Such size reduction methods com- fines through incipient fusion or sintering- monly used in the processing of other industrial often with a Rux. The incorrectly introduced minerals, as ball milling or grinding, would term has persisted and has become entrenched destroy the delicate structure and would render in the particular nomenclature of the trade; and it useless for such applications as filtration or as for historical reasons, its use is being continued ,~ -. 4 a Ratting agent in paint (Fig. 12). here. . ...I.( Since crude diatomite commonly contains as Simple calcining without a flux (straight cal- .. much as 40% moisture, and in many cases over cining) results in a product with a pink cast. ;I 60%. primary crushing to aggregate size is fol- .'. ;>.: . #,'' i The color is caused by the oxidation of iron in lowed by a simultaneous milling-drying as the the crude and becomes more intense with an 1 suspended particles of diatomite are carried in a increasing iron oxide content. Flux calcining 1,. stream of hot gases. Passage of the suspended produces a white product in good quality di- particles in the hot gases through a series of atomite, in part believed to be caused by the fans, cyclones, separators, and a baghouse re- conversion of the iron to complex sodium- sults in the separation of the powder into vari- aluminum-iron , rather than to the ous sizes, in the removal of waste impurities, oxide. A pinkish cast is often observed in flux. '. and in the expulsion of the sorbed water. "Ra- calcined diatomite, if the amount of flux re- - .. tios of over three tons of crude in place, to one quired for optimum filtration properties is in- :.. on of filter aid product, are not unusual. Di- sufficient to complex all of the available iron. atomite products, so processed without further Calcining and flux calcining produce other treatment, are bagged or handled in bulk as changes in the diatom particle. Among these "natural" milled products. are the loss of the combined water that is part When the adjustment of particle size distri- of the opaline structure, degradation of the bution is required for such applications as fast tertiary and secondary structure of the diatom Iflow rate filter aids, the heating of the powder valve through incipient fusion, aiid conversion. .- to incipient fusion in large rotary kilns, fol- of portions of the otherwise amorphous silica. lowed by further milling and classifying, results lo cristobalite (Figs. 13a-d). F Iin straight calcined grades. Further adjustment Filter aid powders for special uses are pro- Diatomite 693

iition of a calcining : a flux is :gh in thi: led. Such ned." term "cal- -ing to the' :ess is not, >f calcina- .eration of intering- introduced mtrenched trade; and continued

, . .. . ,o " ,. , .. .A! . . raight cal- . .- pink cast. of iron in e with an calcining quality -di- .ed by the i sodium- fin to the :ed in flux ,f flux re- ;ties is in- lable iron. luce other long these iat is part .m the of IY .he diatom :onversion .lous silica FIG. 13-Scanning electron micrograph of flux-cnlcined Lompoc, CA. diatomite illlrs- trating agglomeration of fine particles and incipient firsiorl of siliceorrs s1rfcct:rre. .s are pro- 694 Industrial Minerals and Rocks

FIG. 14-An alumi- attribute num, pneumatic, . dry tion. Fi bulk tanker on semi ing degr, and full trailers .Jar and at a transporting diatomite then, m: powders. These are measure 1250 cu ft each (8-9 controlk tons) in capacity. Each the resu has its own low pres- chased c sure air system for un- basis, th loading to the custom- To arrk ticle siz er's storage bin. . ..- , .. analysis ;-. tions, pz: duced by acid treatment of dried and milled its the oversized particles, have been removed ' T material, in combination with conventional cal- during processing.'"' This point is treated in terized i .."., related t cination and flux calcination. Specially pre- more detail later. -_,*4' pared diatomite aggregates have also been pro- While the greater portion of diatomite pow- . ' has bee duced for use as supports in gas liquid chroma- ders are packaged and shipped in 50-lh hags, ' processi tography by special sizing to close tolerances, or equivalent metric quantities, in recent years of a H soluble I followed by acid treatment, and by special sur- progress has been made in the pneumatic hulk ' ' face treatments with silanes or silicones to de- handling of diatomite in conjunction with com- . . Food C activate the support surface. The application mercial shipments in hulk hox,cars, in hulk importa of diatomite in brick and in extruded and ag- trucks, and in pressure differential special bulk compos! functior gregate forms has declined in recent years, compartmented cars '87, 2'B (Fig. 14). .: . hence the manufacture of product types in of the other than fine powders is less important. Spe- General into He: cial milling and classifying techniques have _.t Testing and Specifications in oil a been employed in the control of particle size ... .. ' distribution for functional fillers. For the ea- As is common with most industrial minerals, paper b cient control of gloss and sheen in paint, for the testing procedures by which processed di- exampli example, grades of diatomite powders are avail- atomite powders and aggregates are evaluated sured a! able in which the nonfunctional fines, as well and standardized are designed to quantify an ties are .. quality .<.si'-, TABLE 2-Trpe Elimantal Composition of a Typical C.lite@Diatomite Produet. .. .,. . .:>. , turer an tests ar, - prietar? Element Ppm Element Ppm )I Element Ppm I( Element ~ - PPm .. - practic; Antimony (Sb) 2 Gadolinium IGdl <1 Neodymium INdl 20 Tantalum (Tal 20 ' compar Arsenic IAsl 5 Gallium (Gal 5 (Nil, 120' Tellurium (Te) <2 commo Barium IBa) 30 Germanium IGe) <10 Niobium INb) 5 Terbium (Tbl '-<0.2 particul Beryllium IBeI 1 Gold (nul' , <0.5 Ormiurn , co.5 Thallium (TI) 50.5 ThoriumlThl ' 5 lend thc Bismuth (Bi) <0.5 Hafnium (Hfl Palladium IPd) ,,sl Thulium (Tml ,... 0 2 Boron (01 100 Holmium IHol :::: Bromine (Ed 20 Platinum IPtI ' <2 Tin (Snl <1 Indium (In1

20

Use 1973 1974 1975 1976 1977 1978 1979 ' 1980 ~ 1974 Filtration 61 60 60 60 . 59 63 63 86 1975 Fillers 18' 19' 20' 21' 22 * 23 21 21 1976 Insulation 4 5 4 5 5 3 3 . .. :, 3 1977 Miscellaneous 17 16 16 14 14 11 11 10 1978 1979 'The US Bureau of Mines included fillers with miscellaneous until 1978. The split between fillers and 1980 miscellaneous before 1978 is the author's estimate. .. 1981 ' '.+.I . :, Source: UZ Marketing of transporiation on the diatomite indusfry'is

being treated separately in this chapter.,. -:f- The successful marketing of diatomite prod- . .~ . ',. r,"rl tion of susj ,I. ucts by the major producers has depended, to .. ,<' :;w irq; 50% of al a large degree, on their ability to furnish high :.c' into this ap Transportation 1 '. ..'! .' ,__. , ,'.; c ,- caliber technical sales service to the customer. "?" economic s Technically trained sales engineers, supported The low bulk density of processed diatomite ously reduc by research and development organizations, presents unique transportation problems. Since single, if n( have resulted in the solution of customer pro- all American commercial diatomite originates duction problems with the consequent intro- in the western states, and the predominant complex ai duction of a particular diatomite grade to do markets are located east of the Mississippi constitutio: the job. In technical service to the paint in- River, a substantial part of the eastern delivered I impurities dustry, for example, the development of cost cost consists of freight charges. The price per I part that t saving formulations, through the introduction ton of a California processed filter aid delivered aid is of p: into the formulation of specially developed ex- in New York consists, for example, of approxi- the space tender pigments and diatomite grades for con- mately 33% transportation costs. The success- cake, the trol of gloss and sheen, has been of great help ful exportation of American diatomite to Eu- witbin the to paint manufacturers. There can hardly be a rope, Africa, Latin America, and the Far East ping of in- better foundation on which to base sales effort has traditionally been dependent on a reputa- play betw or to assure product performance. A similar tion and a need for superb quality. multi-spec approach in the selection of filter aids to meet With the cost of freight increasing single-spec a specific requirement, or to solve a unique steadily, together with the rising costs of pro- less to ofl problem, has entrenched trade or brand names duction at home, exports have been under con- numerous in the minds of users who have come to demand tinued pressure from the local sources. For,this i example, .- a high degree of quality and of uniformity. reason, the motivation for foreign exploration ! found in t

' ' While this approach has been of considerable by American companies in the major market with its re assistance to industry, and has ultimately bene- areas is apparent. The trend, therefore, toward I tion for t1 fited the consumer, it has made marketing more decreasing exports in future years is to be an- I with regai diflicult for minor producers with an inferior ticipated. The following are typical current Certain le deposit or an untrained sales organization to (May 1981) transportation costs (inland PIUS pletely dii compete in the more sophisticated or demand- ocean freight) from Lompoc, CA, to repre- I species, \ ing applications of diatomite. The small pro- sentative foreign ports: , ,. tioned. pc ducer, however, supplying to a local, or to a \. tions. Fo lower grade market has been able to compete Port Cost per Mt, S for some successfully. This is particularly applicable to Capetown. South Africa 253 depleted) the small foreign producer against American Yokohama, Japan 121 - '. - aid for rc imports. Buenos Aires, Argentina 213 cake was Diatomite powders are traditionally sold as Sydney, Australia 282 i other ear carload, I.c.~,, and warehouse. American- ex- Hamburg, West Germany 179 The nee1 ports are to a large degree sold through distribu- Hull, England 181 filter aid tors. as are diatomite chromatographic sop- solubility ports, both domestically and abroad. Uses - Diator Because of its low bulk, freight and con- types of tainers constitute a substantial part of the cost Filtration: Uy far, the widest use for pro- tions.' '9 to the consumer. The precise effect of the cost cessed diatomite is as a filter aid for the separa- filter aid Diatomite 697 TABLE 5-Exports of Diatomite particles that are to be removed. It is axiomatic in the use of filter aids that as the particle size, - Quantity, 1000 St Value, 1000 $ and thus the flow rate increases, the ability of 1980 - 1974 186 17,541 the filter aid to remove small particles of sus- 66 1975 147 15.314 pended matter decrease^.'^' Conversely, as fil- 21 1976 149 16.832 ter aid particle size and, therefore, flow rate 3 1977 152 18,876 decreases, the ability cf the filter aid to remove 10 1978 . 153 21,463 small particles of suspended matter increases. 1979 170 26,496 - I fillers and The factors that govern which end of this flow .. 1980 173 32,238 rate-clarity relationship is to be emphasized 1981 160 24.397 will depend very much on the type and the Source: US Bureau of Mines particle size distribution of the undissolved Idustry is solids being removed. The best filter aid is that ter. grade that will result in the fastest flow rate (or tion of suspended solids from About the greatest throughput per dollars worth of 50% of all processed diatomite is channeled filter aid) and yet will provide adequate clarity. into this application. Indeed, the probability of The correct clarity must be determined and economic success for a potential deposit is seri- specified by the filter aid user. The calcination ously reduced it cannot he processed into a diatomite if and flux calcination of diatomite powders are single, if not a range, of filter aid products. The ms. Since performed for the purpose of adjusting particle requirements for filter aid suitability are subtly originates size distribution through incipient fusion and by :dominant complex and many. Above all, diatom skeletal agglomeration of the fines and structure to pro- Aississippi constitution and structure, density, and soluble duce a range of flow rates, hence clarities. delivered impurities are principal considerations. The price per part that the skeletal structure plays in a filter The more commonly known applications are delivered aid is of paramount importance. In addition to the use of processed diatomite powders in the f approxi- the space between diatom particles in a filter filtration of dry cleaning solvents: pharma- e success- cake, the interstices and chambers provided ceuticals: beer, whiskey, and wine; raw sugar le to Eu- within the structure play their part in the trap- liquors; antibiotics:"' industrial,'"' munici- Far East ping of impurities. The relationship and inter- pal,"'. and swimming pool waters; fruit a reputa- play between variously shaped particles in a and vegetable juiccs; lube. rolling mill, and cut- multi-species assemblage is also important. A ting oils; jet fuels; organic and inorganic chemi- increasing single-species assemblage of forms often has cals; and varnishes and lacquers. Diatomite has ts of pro. less to offer than an association consisting of also been mixed with asbestos, and with other nder con- numerous different species. The balance, for minerals, and surface-treated and acid-washed . For this example, between pennate and discoid species to improve its effectiveness in special filtration rploration found in the marine earth at Lompoc, together applications. Table 6 lists the physical proper- ir market with its response to calcination and flux calcina- ties of some commercial filter aids. -e, toward tion for the increase in flow rate, is unmatched Fillers: The second largest use of diatomite to be an- with regard to its flow rate-clarity relationship. is that employed as a filler. Although natural .I current Certain lacustrine earths, consisting of a com- milled powders were used to some extent in !land plus pletely different assemblage or of wholly one paint, paper, , and other uses before to repre- species, while lacking the advantages men- there were baghouse grades, later filler applica- tioned, possess other merits for certain applica- tions were the result of product development to tions, For example, the lacustrine earth mined use the baghouse fines that would otherwise be per Mt. f for some years at Terrebonne, OR, (and now discarded as a byproduct of the filter aid manu- 253 depleted) was a favorable fast flow rate filter facturing process. In recent years, however, 121 aid for rotary precoat filtration in that the filter while filler products are usually produced in 213 cake was less susceptible than that made with conjunction with, and as an integral part of the 282 other earths to cracking on the rotary drum. manufacturing process for filter aids, their 179 The need for low density and particularly in specifications and properties are tailored to meet 181 filter aids sold for food processing for low the requirements of a demanding filler market. solubility content is obvious. Indeed, the term "filler" was often used as the Diatomite is processed into filter aids for all catchall term for those uses that were not di- types of food and nonfood processing applica- rected toward filtration. for pro- tions.'" The selection of the proper grade of Lately, however, the expression, luncrional le separa- filter aid depends on the size of the suspended filler, has been set apart and reserved for those porting PrOF fractive inde important a: facture of ai Liquid A cause of th( ing value, h: can absorb Vegetable oil 1 .o 7.0 2.10 235 100 water. Spe catalyst - ~ .. ,, are still "dl -. . addition of .1 - 7.0 2.15 170 135 Apple juice - property CC liquid carri 3.0 7.0 2.15 255 200 Beer and wine and pitch c ~_~_- chemical ir 4.0 7.0 2.15 250 300 Sugar .. ., sulfuric aG Dry cleaning through thc IOIVe"t6, - 'I-- chemicals. etc. '. safer and c 5.0 10.0 2.30 245 500 hartwidely Inertnes: wed filter I-,_-- exceptiona aid) .,. . 94%. Bec 8.0 10.0 2.30 250 750 Grape juice . to most cl

Industrial and . ' 9.0 10.0 2.30 7.40 900 extremely potable water, .. . point of ai Industrial I 9.0 10.0 2.30 245 1350 attributes, wastes :,.: are respor 12.0 10.0 2.30 240 2160 Swimming ~001s rier and : 20.0 8.0 2.30 220 2380 Pharmaceuticals supports : 50.0 10.0 2.30 220 7500 Phmphoric acid in hydro&? lyst used and the I petroleun- wise smooth paint film and to produce a flatting Mild A

effect."l'. "1' Precise particle size control is re- position t quired during production of flatting agents, 'ness suffi since the extreme fines contribute little to the surfaces. flatting effect, but because of their absorption - the fact I do increase the vehicle demand. Particles that a friabili are too coarse, on the other hand, will cause - polish, I: surface blemishes and unsightly spots. This is refined ( not to say that only the structure is important product in this application, Structure is of primary im- polish fo portance, but brightness, absorption, pH, re- strength fractive index, and chemical stability are also calcinati, important. able for The unique structure of the diatom valve .. required makes it useful as an antiblocking agent in Reinfc polyethylene film production, The film is blown -- produce! as an envelope, and while bot, has a tendency verse m for the surfaces to stick together or "block." and in i If a small amount of diatomite (0.05 to 0.5% Silica by weight) of the right particle size distribu- silica an tion is incorporated into the film, the fine par- particul: ticles sticking through the plastic surface pro- in comt vide a mechanical separation or "antiblocking" manufat effect that keeps the surfaces from sticking.I6* highly a As in the flatting of paint, such other sup- Chro Diatomite 699 porting properties as absorption, brightness, re- atomite as a chromatographic support is a fractive index, and particle size distribution are unique development, principally of the 1960% important and must be considered in the manu- and makes use of and illustrates essentially all ,pica facture of antiblocking agents. the properties that have been previously de- cations, Liquid Absorption-Diatomite powders, be- scribed.18’ Structure and absorption account ration cause of their high surface area and low bulk- for its unique capacity to carry sufficient ing value, have a high absorptive capacity. They amounts of the liquid phase.‘8‘ An inert sur- can absorb up to 21% times their weight of ble oil face is required to keep the support from react- t water, Specially processed diatomite powders ing and interfering with the partitioning ability are still “dry” and free flowing even after the of the liquid phase. When properly processed addition of 50% by weight of water. This and treated, diatomite chromatographic sup iuice property contributes to their application as the ports satisfy all these requirements.’8‘. liquid carrier in rug cleaners, pesticide carriers, Miscellaneous4tber applications that make Id wine and pitch control in paper manufacture. In the -. use of the unusual properties listed above in- chemical industry, such hazardous materials as clude anticaking agent on ammonium-nitrate sulfuric and phosphoric acids are converted !aning prills, head composition to control after through the use of diatomite to dry powders for I. glow, welding rod composition, use in battery ak, etc. safer and easier handling and storage. ,videly ’ Inertness-A high quality diatomite has an box separators, and concrete additive ter .I, exceptionally high silica content-as much as to improve workability and reduce bleeding, f,. 94%. Because it is essentially silica, it is inert acetylene containers, and a stabilizer in explo- “ice ,. to most chemical reactions and is resistant to sives, drilling mud additive, and as a condi- .ial and extremely high temperatures, with a softening tioner of animal foods. Table 7 lists the physi- !water, point of about 2600’F. Coupled with its other cal properties of some commercial fillers. The ial attributes, inertness and temperature resistance uses of diatomite are also covered in the chap- are responsible for its utility as a catalyst car- ter on “Fillers, Filters, and Absorbents,” pages ling pgols rier and as an insulation. .Diatomite catalyst 243-257, Volume 1. muticals supports are ideal for the nickel catalyst used oric acid in processes, the vanadium cata- Further Considerations and Trends - lyst used in the manufacture of sulfuric acid, > .. and the phosphoric acid catalyst used in the ,A, Since the United States is self-sufficient, im- petroleum industry. ports of diatomite have been negligible. HOW- flatting Mild Abrasive-Because it is similar in com- ever, depending on the course of foreign ex- >I is re- position to opaline silica, diatomite has a hard- ploration, on processing costs, and on trans- agents: ness sufficient to produce abrasion on metal portation charges, it is conceivable that eastern to the surfaces. However, to this attribute is coupled US- markets could ‘be penetrated’ to some de- orption the fact that the delicate skeletal structure has gree by European or African sources. es that a friability and particle size that causes it to The presence of eastern US occurrences Of I cause polish, rather than to scratch.”* The highly diatomite, while not a threat to western Su- This is refined (or low contaminant) natural milled premacy at present, could become competitive. portant product is ideal for incorporation into silver For certain low quality applications, the marine uy imi polish formulations, and the slightly increased diatomite outcroppings in Maryland and Vir- IH, re- strength or particle integrity produced by flux ginia could have utility. Marked advances in re also calcination makes this type of treatment suit- processing are required before this earth could able for producing the more abrasive effect approach the quality of western deposits. The n valve required in automobile polishes. bog deposits of Florida, New England, and gent in Reinforcing Effectqhe particulate Structure New Brunswick, because of their eastern loca- i blown produces a semireinforcing effect in such di- tion, are intriguing. Advances in dredging tech- ndency verse materials as silicone rubber specialties, nology and in imaginative processing will be block.” and in mechanical rubber goods. required to upgrade these to commercial I 0.5% Silica Source-Because of its high content of potential. istribu- silica and its high surface area, diatomite is a ne par- particularly suitable and reactive form of silica Substitutes :e pro- in combination with lime for the hydrothermal icking” manufacture of lime- insulations and of While diatomite possesses properties and ;ing.ler highly absorptive calcium-silicate powders. characteristics that are unmatched by other forms of silica-indeed by any other type of 31 sup- Chroinatographic Support-The use of di- 700 Industrial Minerals and Rocks mineral PO lost some rials. Whe of preemir tive newcl position ir lite, when has cut in It has tak' alginates, : percentagf applicatiol was appro where inrc role is in cined cla! tially rep1 diatomite talc busin

Tariffs a: There atomite i tries that designati tions ink diatomit, countrie! the respc try. Of variable ample, r . admittec NO. 25- liceous f (for ex. mite). v specific grades, Japan 1. plies to polarizi: i activate tivated catalyst as "Lak ': 1 and ta: The use thr ! straigh flux c2 -other t iI classifi againsi One diatom cation mineral powder-in certain applications, it has authorities under designation 38-03-2, thus in- lost some ground to new and different mate- cluding it with “activated” mineral materials. rials. Where for decades it has occupied a place It cannot he logically argued with any degree of preeminence in the field of filtration, a rela- of scientific accuracy that the flux calcination tive newcomer has appeared to challenge its of diatomite should be visualized as an octi- position in specific applications-. Per- ming process similar to that of clays or carbon. lite, when expanded and milled into a filter aid, Under the. Tax Reform Act of 1969, the has cut into the rotary precoat filtration field. percentage depletion allowance for diatomite It has taken over some markets for sugar, for was reduced from 15 to 14%. alginates, and for pharmaceutical filtration. The percentage of total perlite going into filtration and ~~~l~~ applications has increased steadily to where it

mite), whether or not calcined, of an apparent Acknowledgments specific gravity of one or less.” Flux calcined The author gratefully acknowledges the as- grades, on the other hand, are taxed 4% in . sistance of Arthur B. Cummins, Irene Crespin, Japan under designation 38-03-2. which ap- Celia Kamau, and Ruth Patrick in the cornpila- plies to “ (decolorizing, de- tion of this bibliography, and of these and nu- polarizing, or absorbent) activated diatomite, merous other colleagues within. Manville for activated clay, activated bauxite, and other ac- their valuable suggestions. tivated natural mineral products.” Diatomite catalyst carriers imported into Japan are classed as “Laboratory, chemical, or industrial wares,” Bibliography and References and taxed 6% under designation 69-09-1. Almost all of the references listed herein, The European Common Market countries which by no means includes all those available, use the designation 25-12-00 for natural and are dated 1960 or later. The reader is referred Straight calcined products and 38-03-M) for to the previous editions of Industrid Minerols flux calcined products. Some countries insert and for bib,iographic information prior other figures for the last two digits for further to 1960, classification. There is still no duty charged against these tariff numbers. General One legitimate point of contention among 1. Anon., 1964, “Celite-The Story of Diato- diatomite producers appears to be the classifi- mite,” Johns-Manville Corp. Bullelin FA- cation of flux calcined diatomite by government 41A. 26 UD. 702 Industrial Minerals and Rocks

de la 39. coom’ 2. Anon., 1969, “Diatomite,” Industrid Min- DiatomCes Yougoslavie,” Arch F. on Hydrobiol., Sup. 41 (1); Algolog. Stud. No. ies rrals. No. 18, March, pp. 9-27. of Si 3. Black, J.P., 1971, “The Almost Perfect Kid- 6. DD. 1-10. Chem nappmg,” Reodrrs Digest, Vol. 98, No. 590, 22. Mehta, S.C., et al.. 1961, ’“The Fine Struc- ’ pellict June, pp. 140-144. ture and the Cell Wall Nature of Dintoma tions, 4. Cummins, A.B.. 1960, “Diatomite,” Indus- Hiemole var. mesoden (Ehr.) Grun,” Revue 2463, ,,io/ Minernls mid Rocks, 3rd ed., J.L. Gill- Algol., Vol. 6. No. I, pp. 49-52. 40. cwm son, ed., AIME, New York, pp 303-314. 23. Mehta. S.C., and Venkataraman, G.S., 1961. Bioch 5. Durham, D.L., 1973, “Dtatomite,” in “United “Fine Structure of Diatom Valves 111,” Shell States Mineral Resources,” Professlonal Botanical Magmine of Tokyo. Vol. 74, No. ture Paper 820. US Geological Survey, pp. 191- 875..__~ nn. 248-2S3.~.~ Navic 195. 24. Okuno, H., 1960. “Fine Structure of Diato- lions. 6. Dutra, F.R.. ,1965, “Diatomaceous Earth maceous Earth Particle,” The World through Pneumoconeoss,” Arclzives Environmental 2461. llte Electron Mlcroscope. by Suito, Society 41. Coon Hen/th. Vol. 11, Nov., pp. 613-619; of Chemistry. Tokyo. .. Birch 7. Frankenhoff, C.A., 1970, “Kenite Diato- 25. Okuno. H.. 1960a. “Electron Microscopical Shell mite,” Industrial Minerals, No. 33, June, pp. Study on Fine Structure of Diatom Frus- ture 51-52. tules, XVIII,” Botnnicol Magazine of Navic 8. Frondel, C.. 1962, “Silica Minerals,” Dana’: Tokyo. Vol 73. No. 865-866. DD. 310-316. ’ I SCIWi! system of Mlnerology, Vol. 3, 7th ed., P. r. . 26. Okuno,’ -1962, “Electron Microscopical 287. H.. PP. 2 9. Hartwell, J.W.. and Schreck, V., 1962. “Dia- Studv on Fine Structures of Diatom FNS- 42. Dark tule; XIX.” Botanical Maguzine of Tokyo, slon Of tomite,” Minerals Yearbook, US Bureau Vol. 75, No. 886. pp. 119-226. . ’ : CUlOS 531-536. Mines, pp. 27. Stoermer. E.F., and Pankratz, H.5; 1964. ceedi 10. Petkof, B., 1970, “Diatomite,” Minerals “Fine Structure of the Diatom Amphipleura. venti Yeorbook, US Bureau of Mines, pp. 501- pellucida. I. Wall Structure,” American lorrr- 43. Desi) 503. nnl of Botonv. Val. I. No. 9. OD. 986-990. ‘The 11. Schroeder. H.J., 1970, “Diatomite,” Minerals Frus Facts and 650, 28. Venkataramk, G.S..’and Mehia, S.C.. 1960. Problems, Bulletin No. US Plty- Sciex Bureau of Mines, pp. 967-975. “Fine Structure of Diatom ValvesI,” tomorpkoloRy, Vol. IO, No. 2, pp. 11&118. 44. Dist. Structure 29. Venkataraman, G.S.. et 81.. 1961, “Fine Accl Structure of Diatom Valves-11,” Jorcrnol of VOl! 12. Ahn, Y.-P., and Lee, K.-G., 1960, “Electron lndion Botanicol Society. Vol. 40, No. 2, PP. Ak“ Microscopical Observations on Fine Struc- 271-273. 204 ture of Diatom Which are Collected 30. Venkataraman, G.S., et al., 1962, “Fine 45. uur in the East Coast of Kyung-Pook Province,” Structure of Diatom Valves IV,” Nova Dia Korcon lourno1 of Botany, Vol. 3, No. 2, Hrdwigirr, Vol. 4, No. 1-2, pp, 127-129. No. pp, 26-28, Chemistry 46. Hal 13. Hens, E.M.. and Drew, C.M.. 1967, “Diato- Dia maceous Earth: Scanning Electron Micro- 31. Arehart, J.L., 1972, “Diatoms and ,” Sea Frontiers, Vol. 18, No. 2, Mar./Apr., LI.1 scope of ‘Chromosorb P‘,” Natttrc, Vol. 216, 47. lor No. 5119. pp. 1046-1048. pp. 90-94. . Barashkov. G.K., 1960, “The Chemistry of Sal 14. Drum. R.W., and Pankratz, H.S., 1963, 32. GI’ “Porms Plates in the Punctae of a Small Diatomaceous Algae (Diatomese),” (inRus- Nil Nitzschia,” Microscope mid Crystal Front, sian), Bot. Zlzur., Vol. 45, No. 9, PP. 1350- 1356. w Vol. 14, No. 1, pp. 1-4. 48. Ki IS. Drum, R.W., et 81.. 1966, Electron Micro- 33. Barashkov. G.K., 1962, ’Chemistry of Some inj scopy of Dialom Cells, Helmcke and Krieger, Marine Plankton Diatoms,” Trudy Mwmansk Mersk. Biol. Insr., Vol. 4, No. nn 27-46. DI Diatomeen-Schalen im Electronmikroskopis- R 16 6, 24 34. Berger, L.R., 1971, “Effects .~ chen Bild, Vol. pp. 49. 16. Drum, R.W., 1969, “ElectLon Microscope Pressure on Photosynthesis and Growth 0: K Unicellular Marine Algae and Diatoms. It Observations of Diatoms. Osrcrr. Bot. A Zrirsckrift., Vol. 116, pp. 321-330. ’ Notionol Technicol Information Service. AD-720, Vol. 401, 11 pp. P. 17. CerlaR, J., 1963. ‘‘Submicroscopic Structure 50. L of the Diatom Frustule and Modern Tech- 35. Bernhard, M., and Zattera, A,, 1967, “A Comparison Between the Uptake of Radio- ta nical Considerations,” Sirzber. Ges. Noturf. U Frermde Berlin, Vol. 3, pp. 144-146. active and Stable Zinc by a Marine ,Unncellu- lar Alga,” Symposium on Radroecoh”J v IS. Hade. G.R., 1968, “The Valve Processes of D.J. Nelson, and F.C. Evans, eds., VOl. 2. 51. L the Centric Diatom Genus Tltalossioairn,” pp. 389-398. E Nytr Mag. Botonik, Vol. IS, No, 3, pp. 193- 36. Bogoyavlenskiy, A:N., 1966.. “Distribution I’ 201. and Migration of Dissolved Silica in , c 19. Helmcke. J.G., 1961, “Electron Microscopy lnrernarionol Geological Review, Vol. 9, NO. 52. I and Algae Structures-Versuch Eiaer Ge- 2, pp, 133-153. C staltsanalyse un Diatomeenschalen,” Recenr 37. Calvert. S.E.. 1968, :Silica Balance in the -1 Advunces in Botany, Sec. 3. University of Ocean and ," Narure. Vol. 21% 53. 1 Toronto Press, pp. 216-231. No. 5157, pp. 919-920. I 20. Helmcke, J.G., and Krieger, W., 1963, “Dia- 38. Coombs. I., and Volcani, B.E., 1968. “Stud- I tomeenschalen Im Elektronenmikroskopi- ies on the Biochemistry and Fine Structure schen Bild. 111. Teil,” Phycologlo, Vol. 3, No. of Silica Shell Formation in Diatoms. Silicon 54. 2. p. 84. Induced Metabolic Transients in Navicula 21. Jerkovit, L., 1972, “Uultrastructure des .oelliculosa (Breb) Hike.” Plonta. VOl. 80, frustules de quelques espkes endemiques des pp. 264-279:

7 04 Industrial Minerals and Rocks ldlo cryplico,” Arclr. Mikrobiol.. Vol. 57. tomite! .. No. I. vv. 43-50. the Lo 71. Znbe1in:V.A.. 1960. “The Crystal Structure 89. Geoloj of SiOl in Opal-Containing Rocks of the 10s. GrOS5. .. ., ” ”_“ Volga Region,” Doklody Akademii. Nauk ... Sedimr DI. 9, No. 3, May, SSSR. Val. 125, pp. 1941-1944. Vol. 1. 72. Zabelin. V.A., 1962, ”Examination of Crys- 90. Zhuze. A.P.. 1966, “Siliceous Sediments of 106. Gulyar tal Structure of Silica in and Opal Modern and Ancient Lakes.” Grochc,r~istry “Wzha Containing Rocks,” Zap. Vscs Mincrolog. of Silico. Strakhov. ed.. pp. 301-320. Armen Obrchclresno, Vol. 91, pp. 343-350. VOl. 3: 107. Herbei New Occurrences and Deposits S,&! pp. 5-: Geology 91. Anon.. 1961. “Diatomaceous Earth in Kent- 108. Ichika, 73. Abbott. W. H., 1971, “Diatom Investigations mere Valley, North Lancashire Co., Eng- the Su of Southern Ocean Deep-Sea Cores,” Ant- land,” Chemical Trade Journal & Chemical Sea. arctic Josr,ral of United Stofes, Vol. 6, No. Enginrr~ing(London). Vol. 149. No. 3882. Maru.’ 5, pp. 171-172. Oct. 21. p.912. _. , tule. B 74. Arakyan, T.A.. 1969, “Genesis of Diato- 92 Anon.. l961a. “The Skye Diatomite Depon- 109. Ichika maceous Earth in the Sisian Deposit.” Iz- its.” Clionical Trodc lormol & Chrinicol the..~. Su. W”1iya Nouki 0 Zemle. Akademii Nauk pan S SSR. Vol. 22. No. 5. pp. 91-96. -. Seifu-: 75. Bradbury, J.P., 1972, “Diatoms and Paleo- Institu limnology,” Abstr. in: Transactions, Amer- PP. I- ican Microscopic Society, Vol. 91, No. 1. 110. Khalfi nr. %A Type 76. Bramlette, M.N., 1961. “Pelagic Sediments,” Reach Oceanography. A.A.S. Pub. No. 67, M. The Geology of Northern Skye.” Mcmoir, Searles. ed.. OD. 345-366. Geological Survey of Scotland. Edinburgh. tu1 Ge 77. Calvert, S.E.’ 1964, factors Affecting the H.M. Stationary Office, p. 216. Sibirsl Distribution of Laminated ~i~f~~~~~~~~95. Andrews, G.W.. 1966. “Late Pleistocene 112. Sedimcnls in thc Gulf of C.sltfurnia,” Moriue Diatoms from Trempeolenu Valley. Wisc..” 111. Knerr Gculoh’~01 1Bc Cull 01 Colilorniu, American Professional Paver 523-A. US Geoloeical- Depo! AFI? :f-Ptlroleum ticulopatr. hlcmoor 3, SUNey, pp. AI-A27. Signif pp. 311-JJU. 96. Andrews. G.W..1970. “Late~ ~~Miocene ~~~~~~ Nan-~ ~ No. 9 78. Calvert. S.E.. 1966, “Origin of Diatom-Rich Marine Diatomi from the Lake Kilgore 112. KOZYI Varved Sediments from Gulf of California,“ Area, Cherr Co Nebraska,” Professional toms Joernol of Geology, Vol. 74, No. 5, pp. 546 Paper 683-1, Us Geological Survey, pp. tralia CLI ,“_I_ AI-A24. nii. V 79. Carter. W.D.. 1971, ‘%RTSA-A New Apo- 97. Andrews, G.W., 1970a. “Early Miocene (13. Levin gee for Mineral Finding,” Mining Engineer- Non-Marine Diatoms from the Pine Ridge of Ki

ing, May, pp. SI-53. marbi~~~~~~~ Area, Sioux Co.. Nebraska.”~~~, ~Professional ~~~~~~~~~~~~~ 80. Dymond, J.R., 1966, “Potassium-Argon Geo- Paper 683-E, US Geological Survey, pp. lnstiti chronology of Deep-sea Sediments,” Scicncr. El-El7. 114. Lohn Vol. 152, May 24, pp. 1239-1241. 98. Archibold, N.L., 1966, “ “Late 81. Emiliani, C., and Milliman, J.D., 1966. Deposits of Mineral Co.,.Nevada,” Report 14, Beavt “Deep-sea Sediments and Their Geological Nevada Bureau of Mines, p. 32. Proff Record,” Earth-Science Reviews, Vol. I. No. 99. Barber, H.G., and Carter, J.R., 1971, “An vey. I 2-3, pp. 105-132. Account of Freshwater Diatomaceous 115. Masc 82. Ichikawa. W., 1967, “Fossil Diatoms and Earth from Gordon Road Site, Auckland, dustr Geology,” Joernol of Geological Socieiy of New Zealand, Part 2.“ Microscopy, Journal Jan., lapan, Vol. 73, No. 2, pp. 53-62. of Quekett Micr. Club, Vol. 32, No. I, 116. McC 83. Karaeva, N.I.. 1971. “The Diatoms of the pp. 2&28. “Mal Genus Navicula Bory in the Palaeogene and 100. Barber, H.G., and Carter, J.R., 1972, “An curre Neogene of the USSR,” Botan. Zhrcmal, VoI. Account of Fossil Freshwater Diatomaceous Mine 56, No. 7, pp. 953-962. Earth from Gordon Road Site, Auckland, .- 117. McL 84. Lanskaya, L.V., 1961, “Rate and Conditions New Zealand,” Microscopy, Journal of Que- _I coun of Division of Marine Planktonic Algae un- kett Micr. Club, Vol. 32, No. 5, pp. 141- Penii der Culture’ Conditions,” Primary Prodec- I A7 Que1 lion of Seas and Inlond Watcrs, pp. 328-332. 101. Beck. F.M., 1966, “Diatomite in Maine,” 154. 85. Lohman, K.E., 1961, “Geologic Ranges of - Contriberions to ih~Geology of Maine, 118. Okui Cenozoic Nonmarine Diatoms,” Professional Bulletin IE. Maine Geological Survey, p. 10- Oki Paper 424-D. US Geological Survey, pp. ...17 Vol. 234-236. 102. Charrin. V., 1962, “Les Gisements Francais 119. Olso 86. Margolef, R., 1961, ”Velocidad de Sedimen- de Kieselguhr,” Genie Civil. No. 139, pp. 84- I Mint tacion de Organisms Pasivos de Fitovlanc- 88. I vada lion.” Barccloka In”. Pesqircros 18. pf. 3-8. 103. Endrihinskii, AS.. and Cheremisinova, E.A., I 120. Pete 87. Schrader, H.-J., 1971. “Fecal Pellets: Role 1970. “On Miocene Sedimentary Rocks from _- in K in Sedimentation of Pelagic Diatoms.” Sci- the Vitim Plateau,” Doklady Akademii 1. Ja rncc. Vol. 174. Oct. I, pp. 55-57. Nnrik SSR, Seriya Geol., Vol. 191, Nos. 4- 121. Phai 88. Tasch. P.. 1967. “The Problem of Primarv 6. PP. 885-888. in \ Production in the Seas Through Geologic IM. Ermina, AS.. 1964, “Characteristics of Dia- 3, A r/y,k7logy. n for Di- Ies I,!dus- I. 3. May, iments of &viisrr? 0.

I in Kent- :o., Eng- Chemical No. 3882. re Depos- C/wnicd No. 3850, :s Quater- ,-ord-Occi- t70/OQ Of 103-107. C.. 1966. Monoir. dinburgh. leisfocene ‘J. Wisc..” 3eological :ene Non- Kilgore ofessional !rvey, pp. Miocene ine Ridge ofessional w,PP. 1 Mineral leeport 14, 971, “An omaceous tuckland, ., Journal , No. I, 972, “An xnaceous luckland, I of Que- pp. 141- Maine,” ! Moine-, :y. p. lo- Francais )* PP. 84- iva, E.A.. cks from 4 kademii Nos. 4- s of Dia- 706 Industrial Mine1,ais and Rocks 175. Kranic con Wafer Works Associolion, Vol. 54, NO. Tr. Kovhozsk. Insr. Mineralin Syryo, Vol. Plame, 9, sep., pp. 1109-1119. 3. pp. 231-237. edy, Jc 141. Baumann, E.R., 1965, “Diatomite Filters 158. Peravalov, V.G.. and Alehseeva, V.A., 1961, 176. KollOr for hlunicipal Use,” Journol o/ lhe Ameri- “The Use of Diatomaceous Earth for Pur/- Miner: can Water Works Associo1ion. Vol. 57, fying Water for Crude Oil Production,” yef;yyoe Khozyoistvo, Vol. 39, No. 4, pp. I. No Feb.. pp. 157-180. Dec., i 142. Bell, G.R.. 1961. “Coagulant Coatings Open JL-,,. 177. Ovcha New Applications to Filter Aids,” Proceed- 159. Rankin.Rankin, R.S..R.S., 1960.1960, “Diatomite Water Fil- Diatoi ittg~,22nd Annual Water Works Conference ters for Municipal Suppliers.” Public Works, Akode of Western Pennsylvania, pp. 129-140. Vol. 91. Feb.. pp. 60, 68, 70. 160. Timen. IC. 1970, “Diatomite Filtration.Re- PP. 54 143. Bell, G.R., 1961a. “Use of Coagulant Coated 178. Ovcha Fi!ter Aids,” Paper given at American Water duces Mercury Pollution,” Chemical Engi- Diatoi Works Assn., California Section, Oct. 27, 1 I neering. Vol. 77, No. 27, Dec., p. 77. Dopoi PP. 50 144. Fillei. and Related Uses 179. Strong 161. Anon., 1960. “Jewels of the Sea Help-Blue . tectioi Coral Preserve Lustrous Finishes,” New ’ Earth 145. York Herald Tribune. Sec. II, Mar. 20. p. 4. Vol. 1 162. Anon., 1961, “New Agent Gives Paint Mak- ers Both Fast Dispersion and High Flatting.” Chromatop Power Speciolisl. Vol. 36, No. 4, p. 14. 146. 163. Anon., 1961. ‘The Paint Industry.” Chemi- 180. Anon cal & Engineering News, Vol. 47,.Dec.. ports pp. 3 1-57. John: 147. 164. Anon., 1969. “Celite and Micro-Cel Func- 181. Ane. tional Fillers.” FA-64A. Johns-Manville of si Corp., Apr., 27 pp. sorbs 165. Ammons. V.. 1963. ‘The Dispersed PiEment 56. P 148. Problem.” Industrial & Engineering Chcm- 182. Aru? i.?lrv. Vol. 55. No. 4, pp. 4047. 1960 166. Agronomov, A.E.. and Mardashev, Vu.S.. Abso 1961. “Structure and Activity of Supported Erev; 149. Nickel Catalysts 1. Change in the Structure 172. of the Carrieron Deposition of Nickel,” 183. Ayer: Zlirrrnol Fig. Kliimii. Vol. 35, pp, 1660- High 1670. Packs 167. Bareja, H.. and Ruskiewicz, M., 1972, “New Vol. Possibilities of Diatomaceous Earth in the 184. Bohe Abso 150. tion ’ Liqum 168. cal s 185. Bryr, 151. and SUPP 169. khin 469. 152. 186. Hay: face 170. ports gok,, 153 187. Otte, Mat< 171 loar No. 188. Strai I54 pp. : 189. Vim pp. 30-32. for ...I,. 172. Kadey, F.L... et, al., 1960, “Relationship of Top. 155. Jackson. T.hl.. 196!: “Filter Aids Speed Up Hardness, Friability, and Particle Sm to the Dilficull Fll1r;lrloni. Clwmicol EnRinrering. Abrasive Performance of Diatomaceous Vol hR. No. 6. Mar.. DO. 141-146. 156. Jahreis.’ C.A..’ 1961; ‘“Filter Performance 173. Diatoms under Field Conditions” Chemical Engineer- ing,. Progress, Vol. 57, No. 7, July, pp. 60- 190. Che 0‘. 157. Midivnishivili. O.M., et al.. 1961, “Com- 174. tere parative Study of USSR Diatomites as Filtra- mite in Chemical Specialties.” Soap & Chem- baii tion Material in the Production of Insulin,” ical Specialties, Vol. 42. No. 12. PP. 73-74. 66. ., .,

yo. Vol. A.. 1961, for Pur/- duction,” 0. 4. PP. .ater Fil- c Works. ition Re- .a1 En& 7.

e!? Blue ii New 20. p. 4. int Mak- qatting,’. 14. Cherni- 7. Dec., :I Func- Manvilie Pipment Chem-

’. VUS.. upported Structure Nickel,” 8. 1660- 2, “New I in the Vol. 36, r Prretr nology,’. ducrion. 2, lune, Jf Flat- ?emion,” 40, No. iulation 4gricirl- 47, 49, ermina- a Filler 1 Com- iOlUtI0” Isskdo- *io. IS, ship of ! to the iaceous 6450. tics of ‘E Pre- Ie e t ing , ‘Diato- Chem- -14. 708 Industrial Minerals and Rocks Selected References Since 1974 Deposits and Its Economic Importance in Turkey,” Congress of Earth Sciences, on the 210. Anon., 1974. “A Wide Range of Uses for Old Occasion of the 50th Anniversary of the Skeletons,” lndusrrial Mi,iernls, NO. 86, Nov., Turkish Republic.” Dec. 17-19, 1973, pub- . pp. 9-25. lished by Mineral Research and Exploration 211. Anon.. 1975, “The Industrial Minerals of Institute. Denmark,” Indusrrial Minerals, No. 89, Feb., 224. Meisinger, A.C., 1978-1979, “Diatomite,” pp. 9-29. Minerals YGarbook, US Bureau of Mines, pp. 212. Anon., 1979. “Pilot Project to Produce Oil 313-315. from Diatomite,” World Mining, March, p. 83. 225. Mekinger. A.C., 1980, “Diatomite,” Preprint, 213. Abbott. P.L., and Gastil, R.G., 1979, “Baja Mineral Fncrr and Problems, Bulletin No. California Geology,” Geological Society of 671, USBureau of Mines. 7 pp. America Annual Meeting, San Diego, Nov., 226. Meisinger. A.C., 1982. “Diatomite,” Mineral publ. prepared for field trips IO, 12, 13. and Commodiry Surnmories, 1981, US Bureau of - 26, pp. 107-1 11. Mines, pp. 4647. 214. Alciatore. A.F., et al., 1974, “Advances in 227. Patel, P.P., et al., 1979, “On the Occurren Perlite and Diatomite Filter Aid Research,” of Diatomite from Bhavnagar Area, Gujara Filrrorion and Separorion, March/April, pp. Journol of die Geological Society of India, 121-126. Vol. 20, No. 3, pp. 114-117. Feldspars. 215. Andrews, G.W.. 1976, “Miocene Marine 228. Patterson. K., 1977. “Australian Mineral In- ’,!!,. igneous roc! Diatoms from the Choptank Formation, Cal- dustry-Diatomite,” Minor Merals and Min- !:,: mixtures. T vert County, Maryand,” Professional Paper erols-1975 Review, Australian Bureau of cance are : P-910, US Geological Survey, 26 pp. Mineral Resources. Geology and Geophysics, 216. Basso, A.J.. 1974, “Bulk Handling and Ship- pp. 364-366. matites as I ment of Diatomaceous Earth,” Filrrarion En- 229. Pinto. T.. 1976, “Developments in Beer Fil- bearing imp pineering, Vol. 5, No. 4, pp. IW11, 14. tration,” The Brewer, April, pp. 115-120. : cobbing, an 217. Baudrimont, R.. and Degiovanni, C., 1974, 230. Rowell, H.C.. 1980, “Diatom Biostratigraphy ore contain “Sedimentoligie-lnterpretaljon Paleo-ecolo- of the . Palos Verdes : gique des Diatomites du Miocene Superior de Hills, California,” M.S. Thesis, University of mingled wit L‘Algerie Occidentale,” Academie des Sci- Southern California, 123 pp. hearing imF ences CR. Vol. 279, No. 16, Serie D, PP. 231. Smith, G.R.S., 1975, “Filter Aid Regeneration : from impu. 1337-1 340. and Recovery,” Chemical Engineering Pros- - , mesh. The 218. Blake, E.E.. and Paulsen, M.B., 1978, “Diato- ress, Vol. 71, No. 12, pp. 37-39. mite Filtration Saves Space and Time,” Water 232. Stosur, I.J., and David, A,, 1976; “Petro- matites, ant ond Warer Engineering, May, pp. 27-30. physical Evaluation of the Diatomite Forma- in the Spru 219. Bryant, E.A., and Bailey, D., 1979, “Ozone- tion of the Lost Hills Field, California,” On the wes Diatomaceous Earth Filtration for Treatment Journol of Perroleurn ‘Teclmology, Oct., pp. there is-or of New York City Croton Water Supply,” 1138-1 144. I Proceedings, Pan I, AWWA 1979 Annual 233. Takayama, Y., 1979, “Preparation of Silyated I natural feld Conference, San Francisco, lune 24-29, pp. Celite by a Vapour-Phase Method,” Journal in glass an< 283-299. of Cltromolography, Vol. 178, pp. 63-70. terminolog? 220. Clark, W.B.. 1978, ‘LDiatomite Industry in 234. Tiller, F.M., and Lloyd, P.T., 1974, “Theory a granitic < California,” Colifornlo Geology, Jan,, 9 pp. and Practice of Solid-Liquid Separation,” ture,‘often 221. Coombs, G.. 1980, “Diatomite,” Mining En- Chemical Engineering Dept.. University of ’--, ’ gineering. May, p. 568. Houston, 12 chapters. impurities. 222. Culver. R.H.. 1975, “Diatomaceous Earth 235. Timmermans, D.E.B., 1980, “Porous Old :. aplite for t Filtration,” Cliernical Engineering Progress, Skeletons Playing a Vital Role in Industry,” .I., Montpelier Vol. 71, No. 12, pp. 51-54. South African Mining ond Engineering lour- 223. Erguvanli, K., et al., 1975. “Siliceous Rock no/, Ian., pp. 103-107. :. ,., Accordir. feldspar de (field) and in tilled gr Gillson (1 citing “sp3 transparent readily cle. past been spar, such correct to

* Presid NC. t Ore D Laboratory Asheville. i $ Intern Skokie. IL.