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THE MINERALS OF RUSSIA: 22ND ANNUAL FM-TGMS-MSA MINERALOGICAL SYMPOSIUM.

Introduction

The 22nd Annual Tucson Mineralogical Symposium sponsored by the Friends of Mineralogy, the Tucson Gem and Mineral Society, and the Mineralogical Society of America will be held on Saturday, February 10, 2001 at the Tucson Convention Center. Admission is free and everyone is welcome. Minerals of Russia and the former Soviet Union are the featured minerals at the Tucson Show and are also the subject of the 2001 symposium.

Present-day Russia is a country of over 6.5 million square miles, and the former Soviet Union was much larger. In this vast region are many and varied mineral deposits. The large number and the range of types of mineral deposits coupled with an active mining industry and a long history of mineralogical research have led to an extensive and rich history for the study of Russian minerals and localities. The Saint Petersburg Mining Institute and the associated museum were founded in 1773 and continue their activities today. In more recent years many scientific institutes and university departments were established across Russia to do research in geology and mineralogy. The studies and literature related to Russian minerals and localities are as extensive as those of any country in the world.

The papers presented in this year's symposium cover a wide range of material, from regional studies to individual localities to specific mineral data. There are amateur collectors and professional mineralogists presenting papers. One goal of the Friends of Mineralogy is to bring these groups together, and this symposium is one of the main ways this goal is reached. There are also seven Russian authors or co-authors of papers (also one author from Sweden and one from Japan), making this symposium an international effort.

A continuing problem with Russian mineral localities is the transliteration of the locality names from Russian to English. Different authors have used a variety of spellings for the names of the Russian localities, which leads to some confusion. A complicating factor is that the name of a locality will have a different ending in Russian depending on whether it is the name of a town, a deposit, or a mine. For example, Orlovskiy is the name of a town and Orlovskoye is the name of a deposit. Another source of difficulty is the soft sound in Russian. Some authors ignore it while others use an apostrophe to indicate that the preceding consonant is softened; for example, the use of Norilsk or Noril'sk. A third source of confusion in transliteration is whether to use the Russian vowel in the word or the English vowel which reflects more accurately the Russian pronunciation. I have tried to standardize the names in the abstracts presented here based on Smith and Smith (A guide to mineral localities in the former Sov iet Union, 1995, Mineralogical Record, 26, 517-541) and a National Geographic Map (Russia and the Newly Independent Nations of the Former Soviet Union, March 1993). For a few of the localities, I found no information and the Russian spelling was not available. I am wholly responsible for the spelling of locality names used in the abstracts.

Raymond Grant

Symposium Chairman

Famous Mineral Localities and Mineral Collecting in the Former Soviet Union, Past and Present

Dmitriy Belakovskiy, Curator Fersman Mineralogical Museum

Moscow, Russia

dmz@minmuz.msk.su

Interest in the collecting of fine mineral specimens started in Russia at the beginning of the eighteenth century. Since that time there have been two main periods for the discovery of world-famous localities in Russia. There are political reasons for both these periods of discovery.

A considerable number of localities were discovered in the middle of the eighteenth century. This was the time of the development of Siberia and the far eastern territories of Russia. The great Siberian expeditions, besides discovering many gold, silver and other ore deposits, also found a number of aquamarine, heliodor, topaz and tourmaline occurrences in the Transbaikal and the Urals, the lapis deposits in the Lake Baikal area, the wiluite at Viluy river and many other mineral localities.

The other great period of discovery was in the second quarter of the twentieth century, when valuable additions of outstanding mineral localities were made during the geological investigations of the Kola Peninsula, the Central Asian Republics, the northern Urals and Siberia and other regions of Russia.

We can now describe about 200 important mineral localities in the territory of the former Soviet Union. Approximately a dozen of them produced an enormous amount of crystalline materials and a number of different minerals. The Dal'negorsk area skarn deposits are famous for crystals of sulfides (galena, sphalerite, arsenopyrite, pyrrhotite etc.) and also for exceptional high-quality crystals of quartz, calcite, fluorite, datolite, danburite, ilvaite and others. Kara-Oba, Akchatau and other W-Mo greisen deposits in Kazakhstan have produced excellent crystals of hubnerite, creedite, different kinds of fluorite, topaz, rhodochrosite, bertrandite, pyrite and many other minerals. In the Northern Urals alpine type veins gave us endless varieties of quartz and crystals of axinite, brookite, anatase, rutile, hematite, ilmenite, kainosite, adularia, calcite and more. Two very similar magnesium skarn deposits, one in Sludyanka (Lake Baikal), and the other around Aldan in Sakha-Yakutia, are famous for huge crystals of b lue apatite, phlogopite, pargasite, diopside, spinel, forsterite and zircon. The emerald mines east of Ekaterinburg are well known also for excellent alexandrite twins, phenakite crystals, apatite and spessartine. And located just a couple of miles south of the emerald mines are the rhodingites of the Bazhenovskoe asbestos deposit (a twin of the Jeffrey mine in Canada) with different colors of vesuvianite, grossular, diopside, clinochlore, and huge blue brucite crystals. Kovdor in the Kola Peninsula has yielded magnetite, phlogopite, and forsterite crystals plus a number of crystalline rarities (kovdorskite, bobierite, and manasseite).

Another dozen localities are interesting in terms of the number of mineral species found in one place. There is no competition for the number of species found in the alkaline complexes such as Khibiny and Lovozero in Kola (more than 400 species), Ilmenskie and Vishnevye Mountains in the South Urals (more than 300 species), and the Murun massif in Sakha-Yakutia.

Another three dozen localities are well-known for attractive examples of two to four species. For example, the Murzinka area in the Urals is famous for topaz, heliodor, and amethyst. The Kerch area in the Crimea Peninsula, Ukraine, is famous for vivianite and anapaite.

Finally, the remainder of the localities are known as a source of good specimens for one mineral species such as the tourmaline at Malkhanskiy district, Transbaikal.

During the time of the Soviet Union, mineral collecting was not very popular. This was unfortunate, because many extremely interesting materials (often from the most interesting upper parts of deposits) were crushed during excavation or buried in the dumps because of the lack of interest. The few existing mineral museums and private collectors could not collect all of the minerals available. At the beginning of the 1990's, when the export and trading of minerals became possible, there was a wave of interest and a lot of excellent material was mined and sold abroad. Currently a large number of important mines are closed due to the military and economic collapse. There are still many possibilities for getting fine minerals in Russia today, but the poorly designed licensing system for mining and the senseless export requirements make the hunt for and export of mineral specimens rather difficult.

Alkaline Massifs in Russia and the Former Soviet Union--A Mineral Heaven

Dmitriy Belakovskiy, Curator

Fersman Mineralogical Museum

Moscow, Russia

dmz@minmuz.msk.su

Alkaline massifs contain more mineral species than any other type of deposit. In some of them it is possible to find more than one tenth of all the mineral species known on the earth (about 4000), and these minerals can be found in a small area, sometimes just a few hundred square miles. In most other types of deposits we can find just a couple of dozen mineral species. There are a few exceptions, such as Franklin, New Jersey, and Langban, Sweden, but the number of species found in these localities is still less than the number found in the richest alkaline massifs. One of the main reasons why there are so many different minerals is the chemistry of alkaline magmas. Almost every element of the periodic table is found in alkaline rocks in concentrations above the average concentration of that element in the earth's crust. Only five elements have a lower-than-average concentration in alkaline rocks.

The Khibiny and Lovozero massifs hold the world's record. The number of species found there so far is close to 500. Those massifs have been very well described. Therefore, in this report we will concentrate on lesser-known localities such as the Murun massif in Sakha-Yakutia, the Ilmeno-Vishnevogorskiy alkaline complex in the Urals, the Dara-i-Pioz alkaline massif, Tajikistan, the Oktyabrskiy massif, Ukraine, and a few other locations.

The mineral specimens that come from these localities are not only "ugly rare species," but there are also some beautiful specimens of rare minerals. A brief description of the geological features, mineralogy, local landscapes, and most remarkable specimens will be given.

Kola Peninsula: The Greatest Mineral Treasure of Russia Today

Igor Pekov

Lomonosov Moscow State University

Moscow, Russia

igorpekov@mtu-net.ru

Extensive research has been carried out on the minerals of the Kola Peninsula region of Russia for the past one hundred years. In the Kola region there is an abundance of unique mineral localities in a very small area. These localities represent a variety of different genetic types, and the deposits are characterized by an unusual mineral diversity.

The list of minerals from the Kola Peninsula numbers about 1,000 species, and Kola is the type locality for 180 mineral species. There are economic concentrations of more than 60 elements, which have led to extensive mining in the region; that mining is responsible for the avalanche of new mineral discoveries. More than half of the minerals are found in the world's largest alkaline igneous complex, the Khibiny-Lovozero complex. The Khibiny complex is the type locality for 130 of the 180 type minerals. Giant deposits of apatite and loparite are currently being mined at the Khibiny complex.

Many of the famous Russian mineral localities such as the Urals, Altai, and Transbaikal are of historical interest, but the Kola region is very active and is producing mineral specimens at present. Many of the Kola localities have become classics. Kola is best known for rare minerals, including the new species, many of which are found as large, perfect crystals, the world's best specimens of these minerals.

Among the many deposits of the Kola are the Khibiny-Lovozero agpaitic massif, the alkaline ultrabasic massifs such as Kovdor, Afrikanda, Turiy, and Mys, the amazonite pegmatite of the western Keivy Plateau, and the Li-Ta-enriched Voron'i Tundry pegmatite. Some interesting occurrences are also found in Precambrian metamorphic rocks, and in younger sedimentary rocks.

Mineralogy of the Burpala Alkaline Massif (North of Lake Baikal)

Aleksandr Portnov

Moscow Geological Prospecting Academy

Moscow, Russia

The Burpala alkaline massif has an oval form and covers an area of 230 square kilometers. The rocks of the massif are Paleozoic in age. Burpala, located 100 km to the north of Nizhneangarsk on Lake Baikal, consists of nepheline syenites in the central part and syenites in peripheral parts of the massif. These rocks are intruded into sandy-schistose sediments of Cambrian age. Veins of nepheline syenite pegmatites cut the massif in the central part and syenite pegmatites are present in contact zones with zones of nephelinitization being typical for exocontacts.

The following minerals are found in the nepheline syenites: britholite, titanite, eudialyte, lamprophyllite, and apatite. The syenite pegmatites contain calcium catapleiite, titanium-rich lavenite, lorenzenite, cesium-rich astrophyllite, kupletskite, pyrophanite, leucophanite, strontium-apatite, loparite, calcium-rich seidozerite, strontium-rich and zirconium-rich perrierite, brookite, landauite, murataite, polylithionite, brewsterite, chabazite, monazite, ancylite, bertrandite, vlasovite, hambergite. Melanocerite, ortholavenite, loparite, thorite, thorianite, eudialyte, perrierite, chevkinite, zircon, leucophanite, catapleiite, astrophyllite, tainiolite, calcium-rich seidozerite are found in nepheline-albite phenites at the exocontact.

Mineral associations from Burpala are typical of alkaline massifs with an intermediate position between miaskite and agpaite alkaline rocks; the associations are similar to the mineralogy of alkaline pegmatites from Langesundfjord (southern Norway) and Colorado (USA).

Recent Mining of Minerals and Gems in Russia by Stone Flower Company

Nikolai Kouznetsov

Stone Flower Company

Moscow, Russia

Nikki@hawkaccess.com

The Stone Flower Company was founded in 1986 as a cooperative. It was the first private company in Russia to deal with gems, minerals, and fossils. Its purpose was to send specialists to various parts of the USSR to mine or buy material to sell to the public and to collectors.

Areas of interest included: Kazakhstan--the Altyn-Tyube mine for dioptase; Karaganda and Dzhezkazgan for silver, wolframite, rutilated quartz, rhodochrosite, and other minerals; Itmurundy for jadeite; Ural Mountains near Ekaterinburg--Malyshevo for alexandrites and emeralds; Murzinka for topaz and other minerals; Potanino near Chelyabinsk for sapphire and other minerals; Polar Urals--Raiz for ruby; Kechpel and Pusyerka for jadeite; Far East--Dal'negorsk for fluorite, calcite, axinite, and other minerals.

After the collapse of the Soviet Union there was tremendous chaos in all activities in Russia, and the Stone Flower Company and the nature of its business changed dramatically. These changes involved new personnel, different tasks and goals, and different motivations.

Some of the recent mining activities of the Stone Flower Company include: Polar Urals--Kechpel for jadeite (1993-1994); Ural Mountains--Kakodino mine for demantoid (1995-1998); Caucasus Mountains, Dashkesan mine, Azerbaijan for quartz, epidote, magnetite, calcite, garnet, and amethyst (1996 to present); Caucasus Mountains, Kapuldzhyk, Azerbaijan for rutile (1999 to present); and Pamir Mountains, Kyrgyzstan for ruby, quartz, and demantoid (1999 to present).

Nomenclature of Quartz Color Variations--Pink and Rose

Hidemichi Hori

Hori Mineralogy Ltd.

P.O. Box 50, Nerima,

Tokyo, Japan 176-0013

Massive rose quartz is a common occurrence in nature, but crystals of rose quartz are very rare. The rarity of crystallized rose quartz is one of the mysteries of the mineral world.

Recently, the Russians have been selling synthetic pink quartz as a commercial product, manufactured for the gem market. Research by Russian scientists found that the origin of the pink color of the crystals from Brazil is related to a trace amount of phosphorus in the crystals. The color of the massive rose quartz, on the other hand, is believed to be related to a trace amount of titanium. The Russians have used this information about phosphorus to grow gem-quality pink quartz. It is probably no coincidence that natural occurrences of rose quartz crystals are usually found associated with phosphate minerals, for example the occurrence of childrenite with the pink quartz crystals from Brazil.

It is proposed, based on this information, that massive rose quartz should continue to be referred to as "rose quartz," whereas the crystallized material should henceforth be referred to as "pink quartz," in recognition of the different chromophores.

References

BALITSKY, V. S., et al. (1998) Russian synthetic pink quartz. Gems and Gemology, Spring, 31-43.

Trace Element Zoning in Metamorphic Minerals

Sergei Skublov

Institute of Precambrian Geology and Geochronology Russian Academy of Sciences

St. Petersburg, Russia

Zoned amphiboles and clinopyroxenes in a garnet amphibolite from the Nyurundukan ophiolitic complex, in the northwest Baikal region, have been analyzed by electron microprobe for major elements and by ion microprobe for their REE, Cr, Ti, V, Zr, Y, and Nb content. The samples investigated contain the assemblage homblende + garnet + clinopyroxene +/- plagioclase + epidote + sphene. Rims of blue-green hornblende are found around brown hornblende. This zoning has been attributed to regressive metamorphism consistent with the granulite to amphibolite facies transition. Increasing pressure toward a paleosubduction zone is the probable cause of this regressive metamorphism. Previous work on the thermobarometry suggests that the metamorphic conditions of the Nyurundukan complex were 600 to 650[degrees]C and 10 to 11 kilobars.

The amphibole studied is zoned with regard to both major and trace elements. From the core to the rim Ti content drops by a factor of 2.7. Na and Al increase slightly to the rim and Cr and V remain virtually constant. Zr (factor of 4), Y (factor of 4.5), and Nb (factor of 7) all decrease from the core to the rim. The amphibole core has higher REE amounts than the rim. All the REE decrease in abundance toward the rim by a factor of about 4 to 5, except for the HREE (factor of 10 for Yb).

The clinopyroxenes from eclogitized gabbros are also zoned. The igneous clinopyroxene relicts in the cores are diopsides with relatively high Ti[O.sub.2] contents (approximately 1.2 weight %). The clinopyroxene rims display a strong increase in Na (up to 13 mole percent of jadeite). The REE, Ti and Y in the clinopyroxenes decrease in abundance from the core to the rim at a slightly lower rate than the rate of decrease in the amphiboles studied.

The trace element compositions of the amphiboles and clinopyroxenes reflect a high-pressure metamorphic event. For example, the rims of metamorphic minerals in the eclogites and garnet amphibolites are more strongly REE depleted than the cores of these minerals, which formed during a previous lower-pressure metamorphic stage.

The Crystal Structure and Charge Density Analysis of Kovdorskite ([Mg.sub.2]([PO.sub.4])(OH).3[H.sub.2]O)

Charles H. Lake

Bryan M. Craven

Department of Chemistry

Indiana University of Pennsylvania

Indiana, Pennsylvania 15705

Kovdorskite ([Mg.sub.2]([PO.sub.4])(OH).3[H.sub.2]O) is a mineral named after the town of Kovdor in the Kola Peninsula of Northern Russia. Our particular specimen came from the Precambrian Lovozero Massif, located between Lake Lovozero and Lake Umbozero, and was provided from the private collection of Professor Robert Newnam (Penn State). The mineral is found in pegmatites, which were crystallized from an alkaline magma possessing high concentrations of magnesium and phosphate ions. The ionic structure crystallized in the monoclinic space group [P2.sub.1]/n with the cell dimensions a = 4.724 A, b = 12.729 A, c = 10.134 A and [beta] = 102.22[degrees] with 4 formula units per unit cell.

The [MgO.sub.6] octahedra are arranged in clusters of four units in a raft-like structure, with neighboring octahedra sharing an edge (two formula units per raft). At the center of each raft are two special corners where three octahedra are joined. These corners are occupied by the hydroxyl ions. The tetrahedral phosphate ions form bridges between different rafts of octahedra so as to form a rigid 3-D framework. This 3-D framework possesses tube-like structures perpendicular to the ac face of the crystal. All the water hydrogen atoms are directed into these cavities where they form a system of hydrogen bonds. The hydroxyl ions, which are located in the middle of the rafts, contribute little, if at all, to the hydrogen bonding system.

Kovdorskite was found to be an excellent candidate for charge density analysis. The atoms in the structure of kovdorskite are bound very tightly. This resulted in very small and well-defined thermal parameters and consequently, allowed us to collect Mo K[alpha] diffraction data out to sin[theta]/[lambda] = 1.26 [A.sub.-1]. This corresponds to a resolution of 0.41 A. In this study we will present the electronic charge density in the crystal structure. Electronic deformations have been modeled by the least squares method based upon the pseudo atom model with multipole expansion to the octapole level. The R)[F.sup.2]) for all 9,883 unique reflections was 4.7%. The experimental net charges obtained for the magnesium, phosphate and hydroxyl ions were +1.2, -2.0 and -0.5, respectively. At the saddle points, in the total electron density, the principal values of the curvature are being determined. The results will be of importance in estimating the ionic vs. covalent character of the various bonds.

The New Russian Classics

William Shelton

19 Highland Avenue

Westfield, Massachusetts 01085

During the past ten years the number of mineral specimens from Russia and the former Soviet Union available to the public has increased greatly. A large number of specimens have found their way to the American market. Collectors can buy superb specimens that have been recently produced from several significant localities in this region, and can also buy good-quality older material from the region. Some of these mineral specimens will become "classics." This is one private collector's experience with some of the newly available material. Several examples are included to illustrate the quality of the material and reasons are given why these specimens may or may not become "classic."

Bornite crystals from Kazakhstan are truly exceptional in size, quality, and abundance. These factors will make this bornite a classic. Quartz with inclusions, which has been labeled "strawberry quartz," is also available from Kazakhstan, but there are not enough really high-quality specimens to make it a classic.

Heliodor (golden beryl) from Tajikistan is truly outstanding. There are many specimens with a color and quality that rivals the best heliodor in the world.

The alpine veins of the northern Urals of Russia have produced many fine specimens. The two classics are the axinite specimens that are the world's finest and the quartz "gwindels" which rank among the best ever found.

Another occurrence of note is Dal'negorsk in far eastern Russia. Fluorite, quartz, pyrrhotite, ilvaite, and calcite are found as stunning specimens and in sufficient abundance to supply the major collections in the world. Many unusual quartz specimens are available including orange colored examples unlike any others. The ilvaites are of an exceptional quality.

Tourmaline from the Malkhanskiy Pegmatite District

William B. Simmons

Karen L. Webber

Alexander U. Falster

Department of Geology

University of New Orleans

New Orleans, Louisiana 70148

The Transbaikal region of southern central Siberia is famous for its gem tourmaline. Pegmatites of the Malkhanskiy district are currently being mined, principally for gem-quality polychrome tourmaline. The pegmatites appear to be related to Jurassic granitic plutons that have intruded Proterozoic metamorphic and igneous rocks.

At least 200 pegmatites are located within the Malkhanskiy district. Of these, seven are currently productive. These include the Mokhovaya, Svetlaya, Orieshnaya, Sosedka, Oktyabrskaya, Zapadnaya and Karkadilovaya pegmatites. The most extensive and productive of these is the Mokhovaya pegmatite, which is granitic in composition and contains abundant miarolitic pockets. The pocket mineralogy consists of gem rubellite, bicolor tourmaline, albite and smoky quartz, with minor pink beryl, lepidolite, danburite, cookeite and pollucite. In some pockets tourmaline is coated with a crust of fine-grained danburite. A few pockets contain large (up to 5 cm), gemmy orange danburite crystals. Additional accessory minerals identified in the Malkhanskiy district include manganocolumbite, monazite, ixiolite, struverite, bismuthinite, bismutite, topaz, spessartine, cesian beryl, biotite, amazonite and fluorite. Other minerals reported include xenotime, euxenite, bismutocolumbite, bismutomicrolite, microlite, hambergite, petali te, stilbite and apatite.

A suite of polychrome tourmaline, collected from throughout the Malkhanskiy district, ranges in color from dark pink to yellow to green to brown. Electron microprobe analyses reveal that the tourmalines are principally elbaitic in composition (Fig. 1) with fluorine contents of approximately 0.5 apfu. [*] Color is found to correlate strongly with Y-site chemistry. Pink tourmaline approaches nearly end-member elbaite composition. Green caps and overgrowths on pink tourmaline contain higher total iron and manganese. The unusual yellow-orange to yellow tourmaline has the highest concentration of Mn (up to 8.1 weight % MnO), but contains virtually no iron. Interestingly, yellow tourmaline contains less liddicoatite (Ca) component than do the rims of some elbaite crystals, which contain up to 42% Ca in the X-site. Overall, X-site vacancies are the highest in pink tourmaline, ranging up to 0.3 apfu. Calculated Li concentrations show a strong negative correlation with Mn content in all tourmalines. Although there is variability in the amount of Mn and Ti, there is a general trend of low Mn and Ti in pink tourmalines and high Mn and Ti in most yellow tourmalines. This suggests that the yellow color of Mn-rich, Fe-poor tourmaline may be the result of the [Mn.sup.2+]-[Ti.sup.4+] charge transfer.

The district is characterized by elbaite as the principal lithium mineral (which is more abundant than lepidolite), and by the low abundance of late-stage phosphate minerals. Tourmalines are Mn-rich and F-rich with low X-site vacancies. Elbaite is associated with late-stage danburite and hambergite. Based on these characteristics, the Malkhanskiy pegmatites can be classified as belonging to the elbaite subtype of the rare-element class of granitic pegmatites.

The Malkhanskiy pegmatites have an unusual late-stage chemistry very rich in calcium and boron, as evidenced by the very late crystallization of danburite and hambergite as pocket minerals and overgrowths on miarolitic tourmaline. Tourmaline composition, especially that of the latest tourmaline, is influenced by this enrichment of calcium, which produces elbaite with significant calcium substitution for sodium in the X-site.

Gem Pegmatite and Greisen Deposits of Russia during the Twentieth Century

Peter Lyckberg

BP2785, L-1027 Luxembourg

lyckberg@p&t.lux

Russia has produced some of the finest topaz, beryl, emerald and alexandrite specimens in the world, primarily from the classic deposits in the Urals and Transbaikal. During the twentieth century, renewed mining has taken place.

During the years 1940-2000 the Takovaya district was mined heavily for Be, Ta, Nb and Mo. Many large emerald specimens and alexandrites up to 2cm were found. The Alabashka-Murzinka-Adui gem pegmatites were studied intensively beginning in 1968 and well into the 1990's. During this period exceptional topaz and beryl specimens were recovered. In Transbaikal, the Malkhanskiy Mountain pegmatites were found in the 1970's carrying fine pink, green and yellow tourmaline. Vodorazhdelnye, in the Menza district south of Malkhanskiy, mined for optical quartz, produced green dravite and flawless elbaite bicolor gem pencil tourmalines. In the Borshchovochniy Range deposits mined for lithium produced tourmaline, topaz, and beryl (Savateeva etc.). Beryl has been found at the Urinskoye pegmatite field and tourmaline at the Polymineralnaya vein. Gem heliodor crystals were found sporadically in the Mama district muscovite pegmatites and, together with topaz, native tin and lead, at Orlovskiy. The classic Sherlovaya Gora greis en deposit was mined for Sn and W, and local collectors found beryl, topaz and smoky quartz. At the nearby Adun Chelon pegmatites a few pockets up to 4 x 3 x 2 meters produced smoky quartz crystals up to 240 kg (90 cm), yellow and blue topaz up to 6.4 kg, and some beryl. Further new deposits include the Svetloye tungsten greisen on Chukotka, producing beryls and topaz, and a mica schist north of Vladivostok producing beryl and topaz; recently gem beryl was found at Pitkaranta near the Finnish border.

Gem Pegmatites of Ukraine, Kazakhstan and Tajikistan

Peter Lyckberg

BP2785, L-1027 Luxembourg

lyckberg@p&t.lux

The rapakivi granites of the Korosten pluton in the Ukraine are rich in vuggy pegmatites containing yellowish green to olive-green beryl crystals up to 1 meter and champagne to blue and bi-colored topaz up to many kg in weight. Mining for piezoelectric quartz in Volodarsk (from 6 main shafts connected by main tunnels at the 50, 100 and 150 m level) produced dozens of pegmatites, with pockets to 30 m on each level, until mining ceased in 1996. In Ukraine a little-known pegmatite deposit, possibly mined already by the Scyths near the Krim Peninsula, yields emerald crystals to 2 cm.

In Kazakhstan the Kalban district has produced some fine bicolored green-red tourmalines as well as rare, flawless indicolites to 5 cm. Novoromanovskoye, Bayanolskogo and the Kent massif deposit of zoned pegmatites carry pockets with flawless, large, light purple fluorite and quartz. Akzhailyau massif pegmatites have pockets up to 2 cubic meters with quartz, microcline, cleavelandite and rarely fluorite. Other pegmatites and greisen have yielded beryl up to 15 cm in association with lepidolite, pollucite, amblygonite, spodumene and topaz.

The Pamir pegmatites of Tajikistan occur in the Muzkol'skovo metamorphic complex of the Rangkul' region, the most prolific veins being Chila MiKa, Polychromnaya, Dorozhniy, Amazonitovaya, Fantaziya, Pegmatite-3, and Beryl-7. Surface collecting and exploration work has reveled blue and champagne topaz to 8 cm, blue beryl, multicolored tourmaline, goshenite, gem purple etched scapolite to 4 cm, rare colorless jeremejevite crystals to 2 cm, and white and sometimes partly purple hambergite crystals. In the southwest Pamir the Besdarinskaya Leschosovskaya and Museinaya veins are also miarolitic and mineral-bearing.

Gem Beryl and Topaz of Sherlovaya Gora, Transbaikal, Russia, A Commonly Mislabeled Locality

Peter Lyckberg

BP2785, L-1027 Luxembourg

lyckberg@p&t.lux

The Sherlovaya Gora greisen deposit, discovered in 1723, is the greatest gem beryl producer in Russia. Labels often read "Adun Chelon," "Murzinka," or simply "Ural." In the old days Sherlovaya Gora was seen as part of the Adun Chelon Mountain Range. Specimens were historically brought to trading centers in the Urals and mislabeled. The Sherlovaya Gora beryl crystals are typically heavily striated, color-zoned across the c-axis, and cylindrical in shape due to di-hexagonal and tri-hexagonal faces. Terminations are simple pinacoids. They are greenish blue, blue or green, and rarely yellowish green or true golden heliodor color. Crystals reach a size up to 31 cm by 5 cm. Topaz occurs as white to transparent, non-gemmy, doubly terminated crystals with smoky quartz, and is often found iron-stained with green or purple fluorite.

Adun Chelon mountain is a separate coarse-grained porphyritic granite intrusion with vertical pipe-like pegmatites from 1 meter to a few meters in diameter. These were commonly mined to 20-34 m depth. The area is believed to have been mined since antiquity, and was relocated in 1835. Lovely sharp yellowish green and green hexagonal (Glubokaya Vein) or etched beryl crystals to 25 cm have been found. Typical etching occurs commonly along the edges. Smoky quartz to 90 cm weighing 240 kg have been found in association with tourmaline and large gem topaz (Chastochina vein) in yellow and blue colors weighing 5.6 and 6.3 kg (1989). The mines of Adun Chelon are located in several valleys and along the ridges just south of the Buryat church "Zagan-Obo," also called Kuku-Sirken in the old days. This latter name often occurs on old labels of specimens from the true Adun Chelon.

Chromate Minerals from Berezovskoye Deposit, Ural Mountains, Russia

J. A. McGlasson

The Collectors Stope

9641 East Hickory Tree Drive

Tucson, Arizona 85749

Some of the most colorful minerals known today were originally found in the Berezovskoye gold mine in the middle Ural Mountains, Russia. This deposit is the type locality for five of the known 22 chromate species (cassedanneite, crocoite, embreyite, phoenicochroite, and vauquelinite). The best information indicates that mining in the region began around 1744, as the gold mines were developed. Berezovsk is located approximately 16 kilometers from the town of Ekaterinburg. A second location in the Tochil'naya Gora region (80 kilometers away) also produced chromate minerals during this time. Crocoite was the first of the chromate species to be recognized, by J. G. Lehman in 1766. Lehman called the mineral "nova minera plumbi" from the Tsvetoni mine, where it occurred with ores of gold, copper, lead and silver. The crystals were described as four-sided prisms of bright yellow-orange color with a saffron streak, associated with cerussite and pyromorphite. It was not until 1841 that the name crocoite was used. The name is from the Greek krokos, saffron, because of the saffron-colored streak.

In 1796, N. L. Vauquelin and his assistant Macquart described the element chromium from material found at Berezovsk. Macquart described a dark green mineral occurring with the crocoite from Berezovsk, but thought that it represented a dark mineral described earlier by Lehman. In 1818 J. J. Berzelius described the dark green mineral that occurred in flattened crystals up to 5 millimeters, as vauquelinite.

In 1833, H. R. Hermann described a third chromate from Berezovsk. This mineral, blood-red and tabular in habit, was initially named melanochroite, and later (1839) changed to phoenicochroite. The latter name is in reference to the dark red color, not black as implied by the former name. In 1968, while completing research on lead chromates at the British Museum, Dr. S. A. Williams described embreyite. This was the fourth chromate to be described from the Berezovsk specimens. Embreyite was first recognized in 1880, by F. Pisani, who described the mineral as botryoidal and red-orange with a yellow streak. The mineral was named for Mr. Peter G. Embrey, former curator at the British Museum.

The last chromate species to be described from Berezovsk is cassedanneite. This mineral is known to occur on only one specimen in the museum of the mining university in Paris. F. Cesbron described it in 1988. Cassedanneite occurs as fine, red-orange, flattened pseudohexagonal crystals associated with embreyite in a crack in massive crocoite. The mineral was named for J. P. Cassedanne, at the University of Rio de Janeiro.

In 1885 Arzruni compiled a list of 54 species occurring at the Berezovsk deposits. Several additional minerals have been added since then, but it gives an idea of the wide variety of minerals associated with the deposit. With the large number of species reported from Berezovsk it is surprising that so few specimens of any material, other than chromate minerals, are seen in modem collections. Outside of the Soviet Union, the British Museum may have the best collection of Berezovsk specimens.

References

BUSHMAKIN, A. F. (1996) Crocoite from the Berezovsk gold mines. World of Stones, 10, 28-31.

WILLIAMS, S. A. (1974) The naturally occurring chromates of lead. Bull, of British Museum (Natural History) Mineralogy Series, 2, No. 8, 379-419.

Nickel and Platinum-Group Element Deposits at Noril'sk, Siberia

J. A. McGlasson

The Collector's Stope

9641 East Hickory Tree Drive

Tucson, Arizona 85749

Rosie Moore

Pan American Silver Corp.

1500 - 625 Howe Street

Vancouver, British Columbia, V6C 2T6 Canada

The Noril'sk region is located near the 70th parallel, on the southern end of the Taimyr Peninsula. In this very hostile environment, where average temperatures are below 0[degrees]C for more than nine months of the year, a world-class copper-nickel-platinum deposit is being exploited. In 1998 Noril'sk Nickel, the largest metal mining company in Russia, produced approximately 19% of the world's nickel, 40% of the platinum, 24% of the palladium, 20% of the rhodium, and 6% of the cobalt from deposits in this region.

Copper-nickel ore was known from the area in the 17th century, but exploration and exploitation did not begin in earnest until the 1920's. In 1935 the "Noril'sk Combine" cooperative was founded and produced the first nickel matte in 1939. The Noril'sk Combine produced metals from the area until 1989 when the Council of Ministers of the USSR passed a resolution making Noril'sk Nickel a "State Concern For Non-Ferrous Metals Production." In 1994 the company was privatized to a Russian Joint Stock Company and shares distributed to over 250,000 persons. The state held the majority of the shares until 1997 when they were transferred to Uneximbank as part of a mortgage auction.

Ore from this region is produced from several mines (including the Medvezhy Ruchey and Zapolyarniy pits and the Taimyrskiy mine) to 1,500 meters depth. The Talnakh and Oktyabr'skoye deposits are hosted in a series of Late Permian to Early Triassic flood basalts and associated ultramafic intrusions. This 3.5 kilometer-thick volcanic sequence consists of alternating lavas and tuffs. The Noril'sk intrusions have several characteristics which set them apart from other PGE (platinum group elements) source rocks: (I) They contain 2-10% of their total mass in sulfides; (2) These sulfides contain a very high concentration of PGE; (3) There are very large contact metamorphic halos surrounding the intrusions; and (4) the sulfur isotope ratios suggest that the sulfur may have originated in-part near the surface as opposed to the mantle. The sulfide platinum-copper-nickel deposits form a series of different ore horizons with varying composition and internal structure within the differentiated intrusions of the Noril'sk type.

Disseminated ores are confined to the lower differentiates (the structure determined by the morphology of the host rocks) with thicknesses of up to 50 meters. The disseminated ores contain the lowest total PGE concentrations but the highest concentrations normalized to sulfide content. The majority of the platinum (90-95%) in disseminated ore is found as sperrylite, with 1.2 ppm in pyrrhotite and pentlandite. Palladium is primarily concentrated in pentlandite (50-1000 ppm); palladium minerals rarely occur in disseminated ore. Rhodium, iridium, and osmium occur as solid solutions in pyrrhotite and pentlandite.

Massive ores occur near the margins of the intrusions and can extend laterally (several hundred meters) into the surrounding late-Paleozoic host rocks. They range from a few centimeters to 45 meters in thickness. The massive ores are the most important economically. The sulfide assemblage is complexly zoned with differing ratios of chalcopyrite, pyrrhotite, pentlandite, and cubanite representing the Cu-Fe-S assemblage. The PGE mineralogy in the massive ores is controlled by the dominant Cu-Fe-S mineralogy. Platinum massive ores occur as sperrylite in pyrrhotite ores and as tetraferroplatinum, rustenburgite, maslovite and moncheite. Palladium occurs as solid solutions in pentlandite, and as discrete minerals, especially in the chalcopyrite ores where minerals of the complex Pd-Pt-Cu-Sn-As assemblage form. Rhodium, iridium, ruthenium and osmium are nearly always concentrated as solid solutions in sulfides, with ruthenium rarely being represented as hollingworthite.

Veinlets in metamorphic rocks form a distinct aureole around the massive ores and are found as 2 to 3-meter-thick lensoid-to-layer-shaped bodies generally concordant with the host rocks. There is a distinct compositional zoning of these veinlets, from pyrrhotite-chalcopyrite-pentlandite near the intrusion to a chalcopyrite-millerite-bornite assemblage distal to the intrusive. Ores in the millerite-bornite portion of the assemblage show the highest PGE content. Platinum is represented mainly as sperrylite. The PGE assemblage forms a complex series of arsenides, stibio-arsenides, arsenostannides, stibiostannides of palladium.

Veinlets in intrusive rocks form 2-5 meters away from the lower contact of the massive ores, as lenses and layered bodies parallel to the lower contact of the massive ore. These ores show a zonation from chalcopyrite-pyrrhotite to chalcopyrite [+ or -] cubanite. The PGE mineralogy is similar to that of the massive ores rich in chalcopyrite, but the concentrations tend to be greater.

Sulfide-poor mineralization is located near the upper contact of the intrusions where chromite becomes dominant, and sulfides comprise less than 3% of the ore. The PGE mineralization is very fine-grained (less than 20 microns) and comprised of tellurides, telluro-bismuthides, stannides, stibnides and arsenides.

Very fine sperrylite and native platinum crystals are available for the collector; however, the rare platinum, palladium, iridium, rhodium, osmium and ruthenium minerals are found mainly as microscopic grains.

References

LUL'KO, V. A. et al. (1996) Geology, magmatism and sulfide platinum-copper-nickel ores. In Noril'sk Nickel (1996) Geology and Ore Deposits of the Noril'sk Region--Guidebook for the 7th International Platinum Symposium, 1994, 1-67.

NALDRETT, A. J. (1994) The Sudbury Noril'sk Symposium, an overview. In Proceedings of the Sudbury Noril'sk Symposium (editors P. C. Lightfoot and A. J. Naldrett) Ontario Geological Survey Special Publication No. 5, 3-8.

STEKIN, A. I. (1994) Mineralogy and geochemical characteristics of the Cu-Ni ores of the Oktyabr'sky and Talnakh deposits. In Proceedings of the Sudbury Noril'sk Symposium (editors P. C. Lightfoot and A. J. Naldrett) Ontario Geological Survey Special Publication No. 5, 217-230.

Mines and Minerals of Dal'negorsk, Russia

Raymond Grant and John Weide

Mesa Community College

1833 W. Southern Avenue

Mesa, Arizona 85202

Viktor Korchevskiy

Perbomayskaya St. g2, kv 25

Dal'negorsk, Russia

Mines in the region of Dal'negorsk, Russia, have produced world-class specimens of calcite, danburite, datolite, fluorite, ilvaite, quartz and pyrrhotite. They have also produced good specimens of apophyllite, chalcopyrite, galena, hedenbergite, manganaxinite and sphalerite. Over 150 different minerals are reported from the mines in the Dal'negorsk area. The town of Dal'negorsk is located a little over 300 km northeast of Vladivostok and about 35 km from the sea of Japan.

The Dal'negorsk mineral deposits were discovered in 1872 by the Chinese. They mined in the area for silver and used some of the borosilicates for glass. In 1887 the Russians settled the region and started mining. In 1924 the mining rights were sold to a British Company, Tetyukhe Mining Corporation. After the English left in 1931, the Russians started to mine lead and zinc again. In 1946 the massive datolite ores were sampled and eventually they were mined as a source of boron. At present there are two companies operating in Dal'negorsk: the Bor Company that operates the Bor open pit mine for boron, and Dal'polymetal that has three underground mines for lead, zinc, bismuth, silver, cadmium and indium.

There are eight mines that have produced mineral specimens in the area close to Dal'negorsk (within 15 kilometers). Today, four of these mines are operating and four are closed. The Bor pit or quarry, the only operating open pit in the area, is being mined for datolite as a source of boron (mainly for boric acid). The Danburitiy mine is an abandoned open pit mined briefly for boron. It is the only locality where danburite has been found. The First Sovietskiy mine opened in 1934 and closed about 1965. The Second Sovietskiy mine also opened in 1934 and is operating at present. (The name Second Sovietskiy is used for a series of mines including Eastern Partizan mine, Western Partizan mine, and Svetly Otvod mine.) The Sentyabr'skiy mine opened in the early 1930's and has been closed for 30 years. The Verkhniy mine was the first mine in the region; mining by Russians started in 1897 and is still underway; it was operated first as an open pit mine (even before 1897 by the Chinese) and is now an underground mine. T he surface workings are still accessible to collecting. These surface workings are also referred to as the Brenner mine (Hamet and Stedra, 1992). The Nikolaevskiy mine opened in 1982 and at present is the largest producer in the district. The Sadoviy mine closed in 1997 and only a few mineral specimens were found in the past.

The geology of the Dal'negorsk region is complex because of its plate tectonic history of repeated accretion and subduction processes. The oldest rocks in the area are limestones, sandstones and siltstones of Upper Triassic to Upper Jurassic age. They were pushed into their present position as a result of the subduction under the East Coast of Russia. Overlying the sediments are Cretaceous tuffs. All of these rocks are faulted and are intruded by a series of igneous rocks. The first was a Late Cretaceous-Tertiary andesite-granodiorite complex associated with the sulfide deposits. This was followed by two series of Tertiary intrusions associated with the boron mineralization in the region (Lisitsyn and Malinko, 1994). The major host rocks for the sulfide and boron deposits are skarns. The primary skarn minerals are wollastonite, hedenbergite, garnet (andradite-grossular), and manganaxinite. The altered skarns contain in addition datolite, hisingerite, quartz, calcite, sepiolite and siderite (Bulavko, 1984). T here are many combinations of these minerals in the skarns, and they form a very striking rock used as an ornamental stone for mosaics, boxes, tiles, and other decorative purposes.

Also of interest to mineral collectors are the ancient hydrothermal cavities found in the mines. They range in size from a few centimeters across to the size of a house. Because they were present before the intrusion of the last magma, some of these cavities are filled with andesite and other igneous rocks. Others are still open cavities and are the source of many of the fine crystallized mineral specimens.

References

BULAVKO, N. V. (1984) Relationship between skarns and hydrothermal polymetallic ores. In Dal'negorsk Ore District Geology, Krasnov, E. V. and Buriy, G. I., editors. Vladivostok, p. 125-136 (in Russian).

HAMET, M., and STEDRA, V. (1992) Die blei-zink-und borlagerstatte Dalnegorsk in Ostsibirien. Mineralien Welt, 6, 46-53.

LISITSYN, A., and MALINKO, S. (1994) The Dal'negorsk boron deposit: a unique mineralogical object. World of Stones, 4, 30-40.

(*.) apfu = atoms per formula unit
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Title Annotation:22nd Annual Tucson Mineralogical Symposium sponsored by the Friends of Mineralogy, the Tucson Gem and Mineral Society, and the Mineralogical Society of America
Publication:The Mineralogical Record
Geographic Code:4EXRU
Date:Jan 1, 2001
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