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The research was performed in the south-eastern part of Russia. Soils were formed on clayey parent materials under an extreme continental climate favorable for the deep freezing and maintenance of permafrost. Based on morphological, micromorphological, physical and chemical attributes, the soils represent a soil complex that includes Vertic Luvic Phaeozems (Clayic and Turbic) and Luvic Phaeozems (Clayic and Turbic). Decomposition, aggregation, eluviation, illuviation, pedoturbation, mineralization and hardening result from accumulation and transformation of organic matter, freeze-thaw, shrink-swell, and translocation processes, and cryoturbation. The soil complex is interpreted as polygenetic. Interpretations were made in order to differentiate modern soil processes from relict ones. The most ancient features correspond to the cold Pleistocene glacial period and include cryogenic wedges, permafrost involutions, disrupted soil horizons, cryogenic sorting of coarse material, and accumulation of the organic matter above the permafrost. A subsequent stage of pedogenesis under a warmer and wetter environment is reflected by black humus crack infillings, black humus aggregates deep in the subsoil, vertical translocation of mobile organic matter, and the formation of clay coatings. Finally, the current climate is a warmer but more arid pedoenvironment. It is recorded in the soil complex by brownish fulvic humus and the formation of vertic features. Even in this last relatively warm climatic stage, vertic features formed by shrinking and swelling processes co-exist with annual deep freezing of the soils and subsoil permafrost at a depth of about ~300 cm., Esta investigação foi realizada na parte sudeste da Rússia, e os solos em causa formaram-se sobre materiais parentais argilosos em condições de clima continental extremo favorável à congelação dos níveis profundos do solo e à manutenção do permafrost. De acordo com as suas características morfológicas, micromorfológicas, físicas e químicas, os solos representam um complexo que inclui Phaeozems Vérticos Lúvicos (Argílicos e Túrbicos) e Phaeozems Lúvicos (Argílicos e Túrbicos). Os processos de decomposição, agregação, eluviação, iluviação, pedoturbação, mineralização e endurecimento resultaram da acumulação e transformação de material orgânico, congelação-descongelação, contracção-expansão, translocação e crioturbação. Interpretou-se o complexo do solo como sendo poligenético. As interpretações foram feitas para diferenciar os processos de pedogénese modernos dos antigos. As características mais antigas remontam ao período glaciar frio do Pleistocénico e incluem cunhas criogénicas, involuções do permafrost, horizontes edáficos desorganizados, distribuição criogénica do material grosseiro e acumulação de matéria orgânica sobre o permafrost. Uma pedogénese posterior associada a um ambiente mais quente e húmido reflecte-se no aparecimento de fendas preenchidas com húmus negro, presença de agregados de húmus negro em profundidade, translocação vertical de matéria orgânica e formação de películas de argila. Finalmente, o clima actual é mais quente e mais árido e esse facto reflecte-se no aparecimento de húmus fúlvico pardacento e características vérticas. Mesmo neste último período mais quente as características vérticas formadas por processos de contracção e expansão coexistem com a congelação anual dos solos em profundidade e com o desenvolvimento de permafrost a uma profundidade de ~300 cm., Este estudio se llevó a cabo en el sureste de Rusia. Los suelos están formados sobre materiales arcillosos bajo un clima continental extremo que favorece la congelación de los niveles profundos y mantiene el permafrost. De acuerdo con sus características morfológicas, micromorfológicas, físicas y químicas, los suelos representan un complejo edáfico que incluye Phaeozems Vérticos Lúvicos (Argílicos y Túrbicos) y Phaeozems Lúvicos (Argílicos y Túrbicos). Los procesos de descomposición, agregación, eluviación, iluviación, edafoturbación, mineralización y endurecimiento resultan de la acumulación y transformación de la material orgánica, hielo-deshielo, contracción-expansión, translocación y crioturbación. El complejo edáfico se interpreta como poligenético. Las interpretaciones se han realizado para diferenciar los procesos de edafogénesis modernos de los relictos. Los rasgos más antiguos están datados del periodo glaciar frío del Pleistoceno e incluyen cuñas criogénicas, involuciones del permafrost, horizontes edáficos desorganizados, distribución criogénica del material grueso y acumulación de materia orgánica sobre el permafrost. Una posterior edafogénesis asociada a un ambiente más cálido y húmedo se refleja en rellenos de grietas con humus negro, presencia de agregados de humus negro en profundidad, translocación vertical de materia orgánica y formación de revestimientos de arcilla. Finalmente, el clima actual es más cálido pero más árido y esto se refleja a través de humus fúlvico pardo y la formación de rasgos vérticos. Incluso en este último periodo cálido los rasgos vérticos formados por procesos de contracción y expansion coexisten con la congelación anual en profundidad de los suelos y el desarrollo de permafrost a una profundidad de ~300 cm.

The biggest Eurasian Udokan copper sandstone deposit is being studied now as preparation for future exploitation. Udokan ore is refractory because it is a mixed-technology type of ore. Chalcocite, bornite and chalcopyrite are the prevailing sulphide ores. The major economic minerals in the oxidised part are brochantite, antlerite, and malachite; chrysocolla is distributed locally. Minor minerals are native copper and cuprite, while the list of rare minerals consists of more than fifty species. In addition to the predominant forms of oxidised copper, general technological problems during flotation are related to sulphates such as brochantite and antlerite. Using X-ray analysis on more than three thousand samples, the average content of major oxidised copper minerals and their local variability for the western area of the Udokan deposit was estimated. The amount of copper in sulphates, 66%, exceeds the 34% in carbonates. Diversity of minor and rare minerals is investigated., The biggest Eurasian Udokan copper sandstone deposit is being studied now as preparation for future exploitation. Udokan ore is refractory because it is a mixed-technology type of ore. Chalcocite, bornite and chalcopyrite are the prevailing sulphide ores. The major economic minerals in the oxidised part are brochantite, antlerite, and malachite; chrysocolla is distributed locally. Minor minerals are native copper and cuprite, while the list of rare minerals consists of more than fifty species. In addition to the predominant forms of oxidised copper, general technological problems during flotation are related to sulphates such as brochantite and antlerite. Using X-ray analysis on more than three thousand samples, the average content of major oxidised copper minerals and their local variability for the western area of the Udokan deposit was estimated. The amount of copper in sulphates, 66%, exceeds the 34% in carbonates. Diversity of minor and rare minerals is investigated.

The article reveals the main factors that had an effect on peopling the territory of Eastern Transbaical. Migrants' conduct towards the existing toponymic system is analysed. An attempt to single out the characteristic features and the main groups of XVII-XIX century Russian toponomy on the territory of Eastern Transbaical is made.

Copper deposits in the region are subdivided into three genetic types, formed from the Early Proterozoic to the Late Mesozoic: Cu in sandstones, as at Udokan; Cu-Ni sulphide ores in gabbros, as at Chiney; and native Cu in volcanic rocks as at Chukchudinsky rift. Economic mineralisation is very localised, the position of the magmatic deposits having been controlled by the same concentrically zoned structures and general faults that determined the placement of sandstone-hosted Cu. The chemical compositions of the various deposits are very similar, all having much more Cu than Ni, Au, Ag or PGE. It is concluded that the anomalous concentrations of Cu resulted from remobilisation by basaltic magmas at different stages of geological history., Copper deposits in the region are subdivided into three genetic types, formed from the Early Proterozoic to the Late Mesozoic: Cu in sandstones, as at Udokan; Cu-Ni sulphide ores in gabbros, as at Chiney; and native Cu in volcanic rocks as at Chukchudinsky rift. Economic mineralisation is very localised, the position of the magmatic deposits having been controlled by the same concentrically zoned structures and general faults that determined the placement of sandstone-hosted Cu. The chemical compositions of the various deposits are very similar, all having much more Cu than Ni, Au, Ag or PGE. It is concluded that the anomalous concentrations of Cu resulted from remobilisation by basaltic magmas at different stages of geological history.

The richest and most prospective of Russia's nine beryllium ore provinces is in western Transbaikal, where ore grades reach 1.3% BeO. Deposits such as Ermakovskoe, Orot, Aunik and Amandak are located in an 800 km strip and are normally associated with early Mesozoic mid-alkaline and alkaline granitoids and bimodal volcanic rocks. The Ermakovskoe bertrandite-phenacite-fluorite deposit, which has the largest Be potential, is confined to a small block of strongly metamorphosed sedimentary rocks with granites, gabbros, younger basic to alkaline granite dykes and leucogranites. The Orot bertrandite deposit is situated in the peripheral part of a palaeovolcano in porphyrytic leucogranites. The Aunik feldspar-fluorite-phenacite-bertrandite and Amandak thorite-fluorite-phenacite deposits in the east are related to leucogranite and kersantite intrusive rocks or granitoid massifs with syenite to basic dykes. Geological and Rb-Sr isotope analysis of the four deposits shows that graben formation, magmatism and Be ore mineralisation were related to Triassic intracontinental rifting., The richest and most prospective of Russia's nine beryllium ore provinces is in western Transbaikal, where ore grades reach 1.3% BeO. Deposits such as Ermakovskoe, Orot, Aunik and Amandak are located in an 800 km strip and are normally associated with early Mesozoic mid-alkaline and alkaline granitoids and bimodal volcanic rocks. The Ermakovskoe bertrandite-phenacite-fluorite deposit, which has the largest Be potential, is confined to a small block of strongly metamorphosed sedimentary rocks with granites, gabbros, younger basic to alkaline granite dykes and leucogranites. The Orot bertrandite deposit is situated in the peripheral part of a palaeovolcano in porphyrytic leucogranites. The Aunik feldspar-fluorite-phenacite-bertrandite and Amandak thorite-fluorite-phenacite deposits in the east are related to leucogranite and kersantite intrusive rocks or granitoid massifs with syenite to basic dykes. Geological and Rb-Sr isotope analysis of the four deposits shows that graben formation, magmatism and Be ore mineralisation were related to Triassic intracontinental rifting.

Papers are presented from the following sessions: Kimberlite and lamproites (15 papers); Lamprophyres and carbonatites (5 papers); Mantle xenoliths and megacrysts from kimberlites (10 papers); and Xenoliths from non-kimberlitic rocks and mantle geochemistry (6 papers). Locations discussed include: Arkhangelsk; Daldyn-Alakit; Mengyin in Shandong; Cleve, Eyre Peninsula; SW Kaapvaal craton; Wesselton; Benfontein; M1 in SW Botswana; western Minas Gerais; the SW Sao Francisco craton; west Yakutia; Ellendale; Golden, British Columbia; Paraguay; Keewatin; Kruidfontein; Fen, Norway and Alno, Sweden; Roberts Victor (2 papers); Ronda in Spain; northern Tanzania; Kimberley Floors; Venezuela; Williams in Montana; Harrat Hutaymah in Arabia; Vitim in Transbaikal; and Lewis in Scotland. Topics include terminology, accessory REE, Sr, Ba and Zr minerals, crater volcanics/sediments, alkaline intrusions, kimberlite-controlling ones in the uppermost mantle, lamproite pipe evolution, early Proterozoic ultrapotassic volcanism, trace element and stable isotope fractionation of carbonatites, fenitisation, complex mineral textures in bededourite, explosive volcanism, diamond- and graphite-bearing peridotite and eclogite xenoliths, octahedral graphite-bearing pyroxenites, low-Ca garnet harzburgites, isotopic disequilibria in garnet peridotites, chromite macrocrysts, Cr garnet indicators, composite/aggregate megacrysts, chemistry of secondary phases in mantle eclogites, orogenic lherzolite massifs, ultramafic inclusions, xenoliths for picrite-basalt thermobarometry, carbonatite-mantle interaction, continental lithospheric mantle chemistry, and the composition of the primitive upper mantle., Papers are presented from the following sessions: Kimberlite and lamproites (15 papers); Lamprophyres and carbonatites (5 papers); Mantle xenoliths and megacrysts from kimberlites (10 papers); and Xenoliths from non-kimberlitic rocks and mantle geochemistry (6 papers). Locations discussed include: Arkhangelsk; Daldyn-Alakit; Mengyin in Shandong; Cleve, Eyre Peninsula; SW Kaapvaal craton; Wesselton; Benfontein; M1 in SW Botswana; western Minas Gerais; the SW Sao Francisco craton; west Yakutia; Ellendale; Golden, British Columbia; Paraguay; Keewatin; Kruidfontein; Fen, Norway and Alno, Sweden; Roberts Victor (2 papers); Ronda in Spain; northern Tanzania; Kimberley Floors; Venezuela; Williams in Montana; Harrat Hutaymah in Arabia; Vitim in Transbaikal; and Lewis in Scotland. Topics include terminology, accessory REE, Sr, Ba and Zr minerals, crater volcanics/sediments, alkaline intrusions, kimberlite-controlling ones in the uppermost mantle, lamproite pipe evolution, early Proterozoic ultrapotassic volcanism, trace element and stable isotope fractionation of carbonatites, fenitisation, complex mineral textures in bededourite, explosive volcanism, diamond- and graphite-bearing peridotite and eclogite xenoliths, octahedral graphite-bearing pyroxenites, low-Ca garnet harzburgites, isotopic disequilibria in garnet peridotites, chromite macrocrysts, Cr garnet indicators, composite/aggregate megacrysts, chemistry of secondary phases in mantle eclogites, orogenic lherzolite massifs, ultramafic inclusions, xenoliths for picrite-basalt thermobarometry, carbonatite-mantle interaction, continental lithospheric mantle chemistry, and the composition of the primitive upper mantle.

The history of uranium production in the former Soviet Union is reviewed and Russian mine production and supply up to 2020 and beyond is discussed, with particular reference to the Danur plant's processing of deposits in the Transural region, the Khiagda deposits and plant, the Elkonsk uranium region and East Transbaikal. Prospects for the use of thorium as nuclear fuel are considered., The history of uranium production in the former Soviet Union is reviewed and Russian mine production and supply up to 2020 and beyond is discussed, with particular reference to the Danur plant's processing of deposits in the Transural region, the Khiagda deposits and plant, the Elkonsk uranium region and East Transbaikal. Prospects for the use of thorium as nuclear fuel are considered.

Extended abstracts are presented on metalliferous and gemstone deposits associated with alkali basalts, high-alumina schists and quartzites, ophiolites, serpentinites, mantle plumes and hot spots, and mafic-ultramafic complexes in the Russian Far East and other parts of the world. Locations or regions discussed include Podgelbanochny in Primorye, western Transbaikal, Izu-Ogasawara-Mariana and Tong trench, Sredinny Ridge in Kamchatka, central and south Urals, the Guarani aquifer in Brazil, Serra Geral/Arapey in Brazil and Uruguay, Ouro Preto, Ghundao Hill, Sanarka River, Upper Priamuriye and Alaska. Mineralisation considered includes phosphate minerals, platinum group metals, cobalt, nickel, amethyst, topaz and corundum., Extended abstracts are presented on metalliferous and gemstone deposits associated with alkali basalts, high-alumina schists and quartzites, ophiolites, serpentinites, mantle plumes and hot spots, and mafic-ultramafic complexes in the Russian Far East and other parts of the world. Locations or regions discussed include Podgelbanochny in Primorye, western Transbaikal, Izu-Ogasawara-Mariana and Tong trench, Sredinny Ridge in Kamchatka, central and south Urals, the Guarani aquifer in Brazil, Serra Geral/Arapey in Brazil and Uruguay, Ouro Preto, Ghundao Hill, Sanarka River, Upper Priamuriye and Alaska. Mineralisation considered includes phosphate minerals, platinum group metals, cobalt, nickel, amethyst, topaz and corundum.

Extended abstracts are presented on techniques for the analysis and interpretation of fluid inclusions and on evidence for the origins of granite-related and other deposits in the Russian Far East and elsewhere in the world. Topics include the composition of magmas and fluids from carbonatites in Transbaikal, the role of colloids (gels and melt-like gels) in the formation of high-temperature endogenous minerals, and studies of particular F-Be, Pt-Cu-Ni, Hg, Sn, W, Fe, talc and chlorite deposits., Extended abstracts are presented on techniques for the analysis and interpretation of fluid inclusions and on evidence for the origins of granite-related and other deposits in the Russian Far East and elsewhere in the world. Topics include the composition of magmas and fluids from carbonatites in Transbaikal, the role of colloids (gels and melt-like gels) in the formation of high-temperature endogenous minerals, and studies of particular F-Be, Pt-Cu-Ni, Hg, Sn, W, Fe, talc and chlorite deposits.

Extended abstracts are presented on granites in the Russian Far East and other parts of the world, their geochemistry and genesis, and their generation of tin, gold and rare-metal deposits. Locations or settings discussed include: the Eastern Blue Ridge in Alabama; Siberia; Mongolia; Kamchatka; the Khasurta pluton; the Kolyvan-Tomsk fold belt and Kuznetsk basin; Muruntau in Uzbekistan; Transbaikal; Pacific marginal seas; the Darya alkaline complex, Aldan shield; the Circum-Japan Sea; the northern Urals; the Orlovka massif; Sikhote-Alin; and the Malkhan system. Mineral occurrences or deposits covered include tin, gold, apatite, fluorite, spodumene, beryllium, topaz, cryolite and gem tourmaline., Extended abstracts are presented on granites in the Russian Far East and other parts of the world, their geochemistry and genesis, and their generation of tin, gold and rare-metal deposits. Locations or settings discussed include: the Eastern Blue Ridge in Alabama; Siberia; Mongolia; Kamchatka; the Khasurta pluton; the Kolyvan-Tomsk fold belt and Kuznetsk basin; Muruntau in Uzbekistan; Transbaikal; Pacific marginal seas; the Darya alkaline complex, Aldan shield; the Circum-Japan Sea; the northern Urals; the Orlovka massif; Sikhote-Alin; and the Malkhan system. Mineral occurrences or deposits covered include tin, gold, apatite, fluorite, spodumene, beryllium, topaz, cryolite and gem tourmaline.

The continent comprises two platforms, the Siberian or Angara platform and the Chinese platform, separated by a huge intracontinental mobile zone consisting of the Baikalides, Caledonides and Hercynides. Representative deposits from the different ore-forming provinces are described and illustrated in cross-section. The Caledonian and Hercynian orogenies in northern Asia gave rise to the deposits of the Urals, the Taimyr metallogenic zone, the Kazakhstan-Mongolian metallogenic zone, the Central Asian metallogenic megaprovince and the Inner Chinese mobile belts. The Tethyan Alpides of Asia include the Caucasian-Asia Minor province, the Iranian-Afghanistani province and the Pamirs-Hindu Kush and Himalayan provinces. The Pacific old Alpides were mainly mineralised during the Kimmerian epoch and include the Transbaikalian metallogenic province, north-east Asia, south-east Asia, China, Vietnam, Indonesia, the Malayan peninsula and the Okhotsk-Chukotka metallogenic zone, while the Pacific young Alpides include the Kamchatka-Koryak zone, the Sikhote-Alin belt, the Japan-Taiwan arc, the Philippines, Indonesia and Burma. Maps show the locations and types of metals and industrial minerals deposits in the former USSR, SW Asia, China and south-east Asia., The continent comprises two platforms, the Siberian or Angara platform and the Chinese platform, separated by a huge intracontinental mobile zone consisting of the Baikalides, Caledonides and Hercynides. Representative deposits from the different ore-forming provinces are described and illustrated in cross-section. The Caledonian and Hercynian orogenies in northern Asia gave rise to the deposits of the Urals, the Taimyr metallogenic zone, the Kazakhstan-Mongolian metallogenic zone, the Central Asian metallogenic megaprovince and the Inner Chinese mobile belts. The Tethyan Alpides of Asia include the Caucasian-Asia Minor province, the Iranian-Afghanistani province and the Pamirs-Hindu Kush and Himalayan provinces. The Pacific old Alpides were mainly mineralised during the Kimmerian epoch and include the Transbaikalian metallogenic province, north-east Asia, south-east Asia, China, Vietnam, Indonesia, the Malayan peninsula and the Okhotsk-Chukotka metallogenic zone, while the Pacific young Alpides include the Kamchatka-Koryak zone, the Sikhote-Alin belt, the Japan-Taiwan arc, the Philippines, Indonesia and Burma. Maps show the locations and types of metals and industrial minerals deposits in the former USSR, SW Asia, China and south-east Asia.

The Baikalide-Altaid and North Pacific orogenic collages (the Transbaikal-Mongolian collages being considered as a detached fragment of the North Pacific) each consist of several oroclinally-deformed magmatic arcs separated by accretionary complexes and ophiolitic sutures located between the major cratons. They exhibit similar tectonic patterns as they were formed as a result of the rotation of the framing cratons and strike-slip translation of the former convergent margins. Distribution of metallogenic belts is similar; in particular, the mid-late Palaeozoic belts of porphyry and epithermal deposits in the Altaids occupy the same tectonic position as the Mesozoic-Cenozoic belts of the North Pacific, and the Ural platinum belt occupies the same tectonic position as the belt of platinum-bearing intrusions in Alaska. The tectonic setting of the orogenic gold belts in the Tien Shan and Verkhoyansk-Kolyma provinces is also similar., The Baikalide-Altaid and North Pacific orogenic collages (the Transbaikal-Mongolian collages being considered as a detached fragment of the North Pacific) each consist of several oroclinally-deformed magmatic arcs separated by accretionary complexes and ophiolitic sutures located between the major cratons. They exhibit similar tectonic patterns as they were formed as a result of the rotation of the framing cratons and strike-slip translation of the former convergent margins. Distribution of metallogenic belts is similar; in particular, the mid-late Palaeozoic belts of porphyry and epithermal deposits in the Altaids occupy the same tectonic position as the Mesozoic-Cenozoic belts of the North Pacific, and the Ural platinum belt occupies the same tectonic position as the belt of platinum-bearing intrusions in Alaska. The tectonic setting of the orogenic gold belts in the Tien Shan and Verkhoyansk-Kolyma provinces is also similar.

Rare-earth and barium-strontium carbonatites in West Transbaikalia, Russia, are associated with potassic alkaline rocks and occur as dykes, sheets and steeply dipping breccia bodies. Bastnaesite phenocrysts in fluorite-bearing carbonatites are thought to be the result of magmatic crystallisation. REE-bearing barium-strontium carbonatites contain apatite, monazite and allanite. Barium and strontium minerals developed as a result of melt liquid immiscibility into sulphate and calcite phases. High fluid saturation of the melt led to further autometasomatic and hydrothermal processes, promoting the formation of a potential ore deposit, mainly of strontium. Interaction between the carbonatites and a fluid phase contributed to shifts in isotopic composition of oxygen, carbon and sulphur. In several deposits, contamination by crustal material has occurred and is observable in the isotopic ratios of oxygen and strontium., Rare-earth and barium-strontium carbonatites in West Transbaikalia, Russia, are associated with potassic alkaline rocks and occur as dykes, sheets and steeply dipping breccia bodies. Bastnaesite phenocrysts in fluorite-bearing carbonatites are thought to be the result of magmatic crystallisation. REE-bearing barium-strontium carbonatites contain apatite, monazite and allanite. Barium and strontium minerals developed as a result of melt liquid immiscibility into sulphate and calcite phases. High fluid saturation of the melt led to further autometasomatic and hydrothermal processes, promoting the formation of a potential ore deposit, mainly of strontium. Interaction between the carbonatites and a fluid phase contributed to shifts in isotopic composition of oxygen, carbon and sulphur. In several deposits, contamination by crustal material has occurred and is observable in the isotopic ratios of oxygen and strontium.

The Altai-Transbaikal and Altai-Okhotsk belts were related to the closure of the Mongol-Okhutsk palaeo-ocean. Metallogenic zoning in the Altai-Transbaikal belt is characterised by rare metal deposits in the west and copper porphyry deposits in the east. Both types of deposit are repeated in the Altai-Okhotsk belt, but have shifted eastwards relative to other corresponding zones. Epithermal Au-Ag, Ag-Sb, U, Hg and CaF2 deposits of Late Mesozoic age are also widespread in this belt. A geodynamic model of the detachment of a subduction slab correlates well with the predominant role of mantle sources and mantle-core interaction as the origin of ore mineralisation, which is confirmed by isotopic Sr87/Sr86 and Sm147 and Nd144 data and the geochemistry of Hg and F., The Altai-Transbaikal and Altai-Okhotsk belts were related to the closure of the Mongol-Okhutsk palaeo-ocean. Metallogenic zoning in the Altai-Transbaikal belt is characterised by rare metal deposits in the west and copper porphyry deposits in the east. Both types of deposit are repeated in the Altai-Okhotsk belt, but have shifted eastwards relative to other corresponding zones. Epithermal Au-Ag, Ag-Sb, U, Hg and CaF2 deposits of Late Mesozoic age are also widespread in this belt. A geodynamic model of the detachment of a subduction slab correlates well with the predominant role of mantle sources and mantle-core interaction as the origin of ore mineralisation, which is confirmed by isotopic Sr87/Sr86 and Sm147 and Nd144 data and the geochemistry of Hg and F.

Precious metal-rich black shales occur at different levels of the Upper Proterozoic and Early Proterozoic volcano-sedimentary deposits. High concentrations of Au (0.5-3.0 ppm) and PGE (0.1-2.2 ppm) are bound to black shales with sulphide mineralisation, and graphite-bearing quartz sulphide metasomatites. Anomalous concentrations of Ag (20-53 ppm) are found in sulphur-free carbonaceous, slightly recrystallised, cherts. The origin of anomalous precious metal concentrations is probably connected with exhalative fluids, forming chemical sediments and replacement ores in black shales and also associated intrusions of alkali rocks., Precious metal-rich black shales occur at different levels of the Upper Proterozoic and Early Proterozoic volcano-sedimentary deposits. High concentrations of Au (0.5-3.0 ppm) and PGE (0.1-2.2 ppm) are bound to black shales with sulphide mineralisation, and graphite-bearing quartz sulphide metasomatites. Anomalous concentrations of Ag (20-53 ppm) are found in sulphur-free carbonaceous, slightly recrystallised, cherts. The origin of anomalous precious metal concentrations is probably connected with exhalative fluids, forming chemical sediments and replacement ores in black shales and also associated intrusions of alkali rocks.

The Ioko-Dovyren dunite-troctolite-gabbro massif is the only large well-preserved layered massif in Siberia and is known for its copper-nickel ores. High platinum group element content was found in rich Cu-Ni ores and recently low sulphide PGE mineralisation has been discovered in the middle section of the massif, mainly in anorthosites. Noble metals are distributed unevenly, but some samples contain noble metals, including gold, up to 10 ppm., The Ioko-Dovyren dunite-troctolite-gabbro massif is the only large well-preserved layered massif in Siberia and is known for its copper-nickel ores. High platinum group element content was found in rich Cu-Ni ores and recently low sulphide PGE mineralisation has been discovered in the middle section of the massif, mainly in anorthosites. Noble metals are distributed unevenly, but some samples contain noble metals, including gold, up to 10 ppm.

Apatites, phlogopites and biotites rich in Cl were found in the intrusive and metasomatic rocks of the Ioko-Dovyren massif which host low-sulphide PGE-bearing horizons. Chlorine-enriched fluid is thought to have had an important role in the formation of the mineralisation., Apatites, phlogopites and biotites rich in Cl were found in the intrusive and metasomatic rocks of the Ioko-Dovyren massif which host low-sulphide PGE-bearing horizons. Chlorine-enriched fluid is thought to have had an important role in the formation of the mineralisation.

The geochemical classification is based on information from granitoids in the ore provinces of Zabaikal, Kazakhstan, the Urals, Yakutia, east Dalniy, Rudniy Gor, the French Massif Centrale, the western USA, Malaysia, Indonesia, northern Nigeria and elsewhere. The trend method of analysing the granitoid series is explained and tin, lithium-tantalum-tin, tungsten, copper and molybdenum trends are identified from a graph of the ratio (Na+K)/Ca against a universal magmatic parameter A(c)., The geochemical classification is based on information from granitoids in the ore provinces of Zabaikal, Kazakhstan, the Urals, Yakutia, east Dalniy, Rudniy Gor, the French Massif Centrale, the western USA, Malaysia, Indonesia, northern Nigeria and elsewhere. The trend method of analysing the granitoid series is explained and tin, lithium-tantalum-tin, tungsten, copper and molybdenum trends are identified from a graph of the ratio (Na+K)/Ca against a universal magmatic parameter A(c).

The structural controls on the distribution of Mo-Cu, Au-U, Au, Au-Mo, Ta-Nb, Li-Be, Pb-Zn-Ag, Pb-Zn + Au, and U-F + Sn-W deposits in the region are considered., The structural controls on the distribution of Mo-Cu, Au-U, Au, Au-Mo, Ta-Nb, Li-Be, Pb-Zn-Ag, Pb-Zn + Au, and U-F + Sn-W deposits in the region are considered.

A geotechnical assessment is made of the region's main deposits: Udokan copper, Bugdainskoye gold-tungsten-molybdenum, Katugin rare metals, Chineiskoye Ti-Fe-V-Cu-Pt, Novoshirokinskoye gold-lead-zinc and Teremkinskoye gold-silver. The mineralogy, geochemistry, treatment method and concentrate recovery for each deposit is listed and discussed. All-round utilisation of mineral resources would require the construction of large centralised mining facilities based on these deposits, as well as regional centres for processing of dump tailings and installations for the treatment of slimes., A geotechnical assessment is made of the region's main deposits: Udokan copper, Bugdainskoye gold-tungsten-molybdenum, Katugin rare metals, Chineiskoye Ti-Fe-V-Cu-Pt, Novoshirokinskoye gold-lead-zinc and Teremkinskoye gold-silver. The mineralogy, geochemistry, treatment method and concentrate recovery for each deposit is listed and discussed. All-round utilisation of mineral resources would require the construction of large centralised mining facilities based on these deposits, as well as regional centres for processing of dump tailings and installations for the treatment of slimes.

Results are presented from a mineralogical and technological analysis of ten samples from equipment installed for the treatment of heavy-mineral concentrates at prospectors' deposits in Transbaikal, Russia. The heavy minerals include cassiterite, zircon, monazite, xenotime, wolframite, ilmenite, scheelite, rutile, cerussite, magnetite and titanomagnetite. The distribution of the various host minerals in the product size fractions is shown. A methodology has been developed for deriving combined flowsheets for the recovery of host minerals. Alternative flowsheets protected by patents are outlined for the production of four additional heavy mineral concentrates apart from gold, Results are presented from a mineralogical and technological analysis of ten samples from equipment installed for the treatment of heavy-mineral concentrates at prospectors' deposits in Transbaikal, Russia. The heavy minerals include cassiterite, zircon, monazite, xenotime, wolframite, ilmenite, scheelite, rutile, cerussite, magnetite and titanomagnetite. The distribution of the various host minerals in the product size fractions is shown. A methodology has been developed for deriving combined flowsheets for the recovery of host minerals. Alternative flowsheets protected by patents are outlined for the production of four additional heavy mineral concentrates apart from gold

The technology for alkaline processing of a wolframite concentrate with sodium hydroxide is described. The concentrate, derived from the polymetallic W-bearing ores of the Transbaikal region of Russia, grades 48.0% W, 9.36% Mn and 5.46% Fe, with traces of Mo, Pb, Bi, As, Sc, U, Th, Nb and Ta. The process flowsheet is presented and discussed. It includes purification of sodium tungstate solutions using VP-18k vinyl-pyridine anionite as a sorbent. This allows recycling of the process water in a closed circuit and produces a high-quality ammonium paratungstate., The technology for alkaline processing of a wolframite concentrate with sodium hydroxide is described. The concentrate, derived from the polymetallic W-bearing ores of the Transbaikal region of Russia, grades 48.0% W, 9.36% Mn and 5.46% Fe, with traces of Mo, Pb, Bi, As, Sc, U, Th, Nb and Ta. The process flowsheet is presented and discussed. It includes purification of sodium tungstate solutions using VP-18k vinyl-pyridine anionite as a sorbent. This allows recycling of the process water in a closed circuit and produces a high-quality ammonium paratungstate.

The current methods of alluvial mining from gold-bearing sands at Ivachikha, Verkhnyaya Davenda and Malaya Borovaya, in NE Transbaikal, Russian Federation, are characterised. The proportion of gold in the 0.25-1 mm fractions is 64% at Malaya Borovaya, 66.6% at Ivachikha and 67.5% at Verkhnyaya Davenda, but gold in the fraction finer than 0.1 mm amounts to 10.06%, 8.95% and 9.14% respectively. Results are reported from the testing of a new machine with three-layer sluice boxes of a new design, developed for the additional recovery of fine and very fine gold. It is shown that it would be possible to decrease losses of gold to the sand-clay wastes by 15-20%., The current methods of alluvial mining from gold-bearing sands at Ivachikha, Verkhnyaya Davenda and Malaya Borovaya, in NE Transbaikal, Russian Federation, are characterised. The proportion of gold in the 0.25-1 mm fractions is 64% at Malaya Borovaya, 66.6% at Ivachikha and 67.5% at Verkhnyaya Davenda, but gold in the fraction finer than 0.1 mm amounts to 10.06%, 8.95% and 9.14% respectively. Results are reported from the testing of a new machine with three-layer sluice boxes of a new design, developed for the additional recovery of fine and very fine gold. It is shown that it would be possible to decrease losses of gold to the sand-clay wastes by 15-20%.

Geochemical mapping is being carried out in Russia at a scale of 1:1 000 000 in a series of stages. The pre-survey stage involves multi-factor zoning of the territory, landscape geochemistry, metallogeny and economic conditions. Within each area, quasi-homogeneous cells are designated and sampling and quantitative analysis of the data carried out. Systematic plotting and publishing of a set of 9-12 thematic maps is then undertaken. The maps allow an understanding of the geochemical nature of the rock assemblages, the mineral potential of the area, ecological situation, soil fertility and chemical pollution levels. The East Transbaikal area, SE Siberia, is used as an example., Geochemical mapping is being carried out in Russia at a scale of 1:1 000 000 in a series of stages. The pre-survey stage involves multi-factor zoning of the territory, landscape geochemistry, metallogeny and economic conditions. Within each area, quasi-homogeneous cells are designated and sampling and quantitative analysis of the data carried out. Systematic plotting and publishing of a set of 9-12 thematic maps is then undertaken. The maps allow an understanding of the geochemical nature of the rock assemblages, the mineral potential of the area, ecological situation, soil fertility and chemical pollution levels. The East Transbaikal area, SE Siberia, is used as an example.