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New Data for Malanite and Cuprorhodsite from Chromitites of the Bushveld Complex, South Africa Geol. Ore Deposits (IF 0.74) Pub Date : 2021-02-08 N. S. Rudashevsky, V. N. Rudashevsky
Abstract The 3D-mineralogical technology was used to study a representative selection of grains of thiospineles from three groups of chromitite horizons (lower LG6, middle MG1/MG2 and upper UG2): 46 grains of malanite (4–42 μm) and 34 grains of cuprorhodsite (9–42 μm). Their microprobe analysis was performed (n = 61). The statistics for this selection of grains have resulted in the following formulas:
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The Symmetry Statistics of Mineral Species in Various Thermodynamic Environments Geol. Ore Deposits (IF 0.74) Pub Date : 2021-02-08 S. K. Filatov
Abstract This paper generalizes the data on the symmetry of minerals in different Earth shells as a function of temperature, pressure, and the combined effects of both parameters. It is shown that the distribution of mineral species in the symmetry hierarchy, in particular, the existence of a monoclinic maximum and a triclinic minimum in the symmetry statistics of the world for minerals and inorganic
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Agates from Paleoproterozoic Volcanic Rocks of the Onega Structure, Central Karelia Geol. Ore Deposits (IF 0.74) Pub Date : 2021-02-08 E. N. Svetova, S. A. Svetov
Abstract Agate mineralization in Central Karelia, Northwest Russia is related to the Paleoproterozoic volcanic rocks of the Ludicovian Superhorizon (2.05–1.95 Ga) within the Onega structure. Agates and parental volcanic rocks were studied with optical and electron microscopy, electron microprobe, X-ray diffraction, Raman spectroscopy, and ICP-MS. It is shown that fine-grained quartz, and fibrous and
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The Niz’yavr Alkaline Pluton: Age, Isotope Characteristics, and Rare-Metal Mineralization Geol. Ore Deposits (IF 0.74) Pub Date : 2021-02-08 M. N. Petrovskiy
Abstract The two phase Niz’yavr alkaline pluton is composed of alkali syenite and alkali quartz syenite. The crystallization age of alkali quartz syenite is 2656 ± 3 Ma. According to the isotope data (Rb–Sr, Sm–Nd), the pluton rocks are mantle-derived. The BSE mantle reservoir was the probable source for their melts, like other Neoarchean alkaline plutons in the Kola Province that belong to the association
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Modeling of Mineral Parageneses and Thermobarometry of Metavolcanic Rocks of the Ruker Group in the Southern Prince Charles Mountains, East Antarctica Geol. Ore Deposits (IF 0.74) Pub Date : 2021-02-08 Yu. L. Gulbin, E. V. Mikhalsky
Abstract Diverse geological complexes that form the crystalline basement of the East Antarctic Platform crop out in the Prince Charles Mountains. The Ruker Group is a member of the metasedimentary complexes that make up the Paleoproterozoic through Neoproterozoic suprastructure of the Ruker Terrane. It is divided into two sequences consisting of highly deformed and greenschist facies metamorphosed
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Finding forms and Micro- and Nanoscale Assemblages of Gold as Indicators of Formation Conditions, Distribution, and Typification of Orogenic Deposits of Uzbekistan (South Tien Shan) Geol. Ore Deposits (IF 0.74) Pub Date : 2021-02-08 R. I. Koneev, R. A. Khalmatov, A. N. Krivosheeva
Abstract—Gold deposits of the Kyzylkum and Nurata regions of Uzbekistan are confined to the South Tien Shan orogenic belt. They are hosted in black shales (Muruntau and Myutenbai); carbonate, terrigenous, and volcanogenic rocks (Kokpatas and Balpantau); and in intrusive units (Zarmitan zone). The age of gold mineralization is 280–290 Ma, which corresponds to the age of postcollisional granitoid magmatism
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Granite Systems with Rare-Metal Pegmatites Geol. Ore Deposits (IF 0.74) Pub Date : 2021-02-08 S. M. Beskin, Yu. B. Marin
Abstract For most rare-metal pegmatite fields, two generations of granitic pegmatites are documented, namely, beryll-bearing (often with tantaloniobates and muscovite, which are inseparable from vein granites of the leucogranite complex), and Na-Li (Li, Ta, Cs, Be, and Sn) (LCT-pegmatites). The latter, in turn, subdivide into (i) a “multicomponent rare-metal type” with pegmatite zoning and main mineralization
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On the Genesis of “White Granite” from the Kester Harpolith, Arga–Ynnakh–Khaya Pluton, East Yakutia Geol. Ore Deposits (IF 0.74) Pub Date : 2021-02-08 V. I. Alekseev, Yu. B. Marin
Abstract—The problem of the origin of “white granite” in the Kester harpolith of the Arga–Ynnakh–Khaya Pluton is discussed. The morphology, occurrence, and nature of the intrusive contacts of the Kester harpolith prove its magmatic origin. The petrographic and petrochemical properties of “white granite” allow its identification as a postorogenic rare-metal high-phosphorus granite of the Li-F geochemical
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The Lu–Hf Isotope Composition of Zircon from Syenites of the Saharjok Alkaline Massif, Kola Peninsula Geol. Ore Deposits (IF 0.74) Pub Date : 2021-02-08 V. R. Vetrin, E. A. Belousova
Abstract Zircon crystals from the alkaline and nepheline syenites of the Saharjok massif, which were formed during the magmatic (2645 ± 7 Ma), hydrothermal (1832 ± 7 Ma), and metamorphic (1784 ± 22 Ma) crystallization stages, were studied. Zircon from alkaline syenites displays lower εHf and εNd values than zircon from ocean island basalts (OIB); these values indicate their affinity to mantle-derived
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New Data on Platinum Group Element Bearing Chromitites from the Kurtushiba Ophiolite, Western Sayan Geol. Ore Deposits (IF 0.74) Pub Date : 2021-02-08 A. N. Yurichev, A. I. Chernyshov
Abstract—Small grains of platinum group minerals (PGMs) have been found in chromitites of the Ergaksky and Kalninsky ultramafic massifs, which are marginal northeastern fragments of the Kurtushiba ophiolite belt in Western Sayan. Along with previously described PGMs, the Cu–Ru–Os solid solution, arsenic-bearing (As up to 3.6 wt %) laurite with minor Pt, Ni, and Co, platinum group element (PGE) sulfides
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The Age of Monazite from the Ichet’yu Occurrence, Middle Timan (CHIME and LA–ICP–MS Methods) Geol. Ore Deposits (IF 0.74) Pub Date : 2021-02-08 A. B. Makeyev, S. G. Skublov, A. O. Krasotkina, S. E. Borisovskiy, T. B. Thomsen, S. H. Serre
Abstract—A study of the morphology, composition, and age (by the CHIME and LA–ICP–MS methods) of monazite from the Ichet’yu occurrence, located in Middle Timan, revealed some principal differences in the typomorphic features and genesis of its two varieties. The common yellow monazite from this occurrence is monazite-(Ce), in which the content of La is higher than that of Nd. The time of its crystallization
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Belogubite, a New Mineral of the Chalcanthite Group from the Gaiskoe Deposit, South Urals, Russia Geol. Ore Deposits (IF 0.74) Pub Date : 2021-02-08 A. V. Kasatkin, S. N. Britvin, N. V. Chukanov, R. Škoda, A. A. Agakhanov, D. I. Belakovskiy
Abstract Belogubite CuZn(SO4)2 ⋅ 10H2O, a new mineral of the chalcanthite group, is found in the Gai (Gaiskoe) massive sulfide deposit, South Urals, Russia. This mineral forms aggregates of blue grains up to 1 mm. It is optically biaxial (–), np = 1.512(2), nm = 1.525(2), ng = 1.531(2), 2V = 70(10)°. The chemical composition of the holotype sample is as follows (wt %): 1.12 MgO, 0.10 MnO, 3.15 FeO
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Wolframoixiolite in Lithium–Fluorine Granites of the Arga–Ynnakh–Khaya Pluton, Yakutia Geol. Ore Deposits (IF 0.74) Pub Date : 2021-02-08 V. I. Alekseev, Yu. B. Marin, O. L. Galankina
Abstract A complex of accessory W-bearing tantalo-niobates (columbite-(Fe), columbite-(Mn), tantalite-(Mn), microlite group minerals, and Ta-bearing rutile) involving “wolframoixiolite” has been found for the first time in Li–F granite and ongonite of the Arga–Ynnakh–Khaya Pluton in East Yakutia. The rocks that contain wolframoixiolite, as well as the composition and typical features of the mineral
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Mineral Systems Based on the Number of Species-Defining Chemical Elements in Minerals: Their Diversity, Complexity, Distribution, and the Mineral Evolution of the Earth’s Crust: A Review Geol. Ore Deposits (IF 0.74) Pub Date : 2021-02-08 V. G. Krivovichev, M. V. Charykova, S. V. Krivovichev
Abstract—The chemical diversity of minerals can be analyzed in terms of the concept of mineral systems based on the set of chemical elements that are essential for defining a mineral species. Only species-defining elements are considered to be essential. According to this approach, all minerals are classified into ten types of mineral systems with the number of essential components ranging from 1 to
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Prenucleus Clusters and Nonclassical Crystal Formation Geol. Ore Deposits (IF 0.74) Pub Date : 2021-02-08 A. M. Askhabov
Abstract—The features of nonclassical nucleation of crystals, which are related to the formation of stable prenucleus clusters of an intermediate phase in a crystal-forming medium, are considered. These clusters (quatarons) are primary protomineral particles, whose crystallization is among the possible scenarios of their evolution. The formation conditions and typical properties of quatarons are discussed
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The Defect-Impurity Composition of Diamond Crystals with 〈100〉 Growth Pyramids from Placers of the Krasnovishersk District, the Urals Geol. Ore Deposits (IF 0.74) Pub Date : 2021-02-08 I. V. Klepikov, E. A. Vasilev, A. V. Antonov
Abstract—The internal structure and spectroscopic features of cuboid diamonds from recent alluvial placers of the Krasnovishersk District (the Urals) have been investigated. Crystals were divided into four groups by their anatomy and spectroscopy: cuboids of the II group (according to the Yu.L. Orlov classification): cuboids with a transparent core and peripheral zone saturated with inclusions; crystals
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Chrome Spinels in Carbonate Veins of the Onguren Complex, Western Baikal Region Geol. Ore Deposits (IF 0.74) Pub Date : 2021-02-08 V. B. Savelyeva, E. P. Bazarova, E. A. Khromova
Abstract Chrome spinels in carbonate veins of the Onguren Complex, East Siberia, Western Baikal region are predominantly ferrichromite and chrommagnetite (MgO ≤ 0.3 wt %, Mg# ≤ 0.04, Al2O3 ≤ 2.5 wt %; Cr# 0.91–1.00, Fe2+/Fe3+ 0.8–1.4) with a high ZnO content (0.9–4.6 wt %). In the calcite vein, titanian chrome-magnetite is transformed into Cr-bearing titanomagnetite, which decomposes into Ti-depleted
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Polymorphism and Isomorphic Substitutions in the $${\text{Cu}}_{3}^{{2 + }}$$ ( T 5+ O 4 ) 2 Natural System with T = As, V, or P Geol. Ore Deposits (IF 0.74) Pub Date : 2021-02-08 I. V. Pekov, N. V. Zubkova, V. O. Yapaskurt, N. N. Koshlyakova, A. G. Turchkova, E. G. Sidorov, D. Yu. Pushcharovsky
Abstract—In the \({\text{Cu}}_{3}^{{2 + }}\)(T5+O4)2 (T = As, V or P) natural system arsenates are trimorphous (lammerite, lammerite-β, and unnamed triclinic Cu3[(As,V)O4]2), as well as vanadates (mcbirneyite, pseudolyonsite, and borisenkoite), while phosphates are represented by a poorly studied lammerite-like Cu3[(P,As)O4]2 phase. In active oxidizing-type fumaroles related to the Tolbachik volcano
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The Mineral Composition of Paleoproterozoic Metamorphosed Massive Sulfide Ores in the Kola Region (A Case Study of the Bragino Ore Occurrence, Southern Pechenga) Geol. Ore Deposits (IF 0.74) Pub Date : 2021-02-08 A. A. Kompanchenko, A. V. Voloshin, A. V. Bazai
Abstract Many massive sulfide ore occurrences and deposits in the Kola region are located within the Paleoproterozoic Pechenga–Imandra–Varzuga rift belt (2.5–1.7 Ga). They are hosted by volcanosedimentary complexes of the South Pechenga (Bragino ore occurrence) and western Imandra–Varzuga structural zones (Pirrotinovoe Ushchel’e deposit, Tahtarvumchorr ore occurrence, etc.). The age of the massive
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The High-Temperature Behavior of Axinite-(Mn), Kornerupine, and Leucosphenite Geol. Ore Deposits (IF 0.74) Pub Date : 2021-02-08 M. G. Krzhizhanovskaya, V. A. Firsova, R. S. Bubnova, S. N. Britvin, O. G. Bubnova, I. V. Pekov
Abstract— In situ high-temperature powder X-ray diffraction (HTPXRD), differential scanning calorimetry (DSC), and thermogravimetry (TG) of three natural borosilicates have been performed in the temperature range of 25–1200°С. Axinite-(Mn) melts incongruently at 900°С with the formation of anorthite and bustamite. Leucosphenite decomposes at 850°С to form fresnoite and cristobalite. According to DSC
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Structural-Morphological Types and Localization Conditions of the Apocarbonate Talc Mineralization in the Beloretsk District of the Western Urals Province Geol. Ore Deposits (IF 0.74) Pub Date : 2021-01-30 N. V. Granovskaya, A. V. Kochergin
Abstract The structural–morphological types and localization conditions of talc occurrences in the Beloretsk district of the Western Urals talc province are discussed. The talc mineralization is represented by low-iron talcites and talc stones in the Riphean clastic–carbonate complexes of the Bashkirian Meganticlinorium. Prospective talc objects in the Beloretsk district are classified as apocarbonate
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The Unique Sabantuy Chromite Paleoplacer in the Sedimentary Cover of the Eastern European Platform Geol. Ore Deposits (IF 0.74) Pub Date : 2021-01-30 I. R. Rakhimov, D. E. Saveliev, V. V. Kholodnov, D. A. Zamyatin
Abstract—In the section of the sedimentary cover of the East European Platform, the new Sabantuy chromite ore occurrence was revealed. It is localized in Upper Kazanian sandstones of the erosional terrace above the floodplain of Malaya Berkutla Creek in the south-west of the Republic of Bashkortostan. The article presents the first results of geological, lithological, and mineralogical–geochemical
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Dissolution of Natural Octahedral Diamonds in an Fe–S Melt at High Pressure Geol. Ore Deposits (IF 0.74) Pub Date : 2021-01-30 V. M. Sonin, E. I. Zhimulev, A. A. Chepurov, E. S. Lindenblot, A. M. Logvinova, D. V. Shcheglov, B. S. Pomazanskii, V. P. Afanas’ev, A. I. Chepurov
Abstract—An experimental study was carried out on the dissolution of natural octahedral diamonds from the Internatsionalnaya and Yubileinaya kimberlite pipes (Yakutia) in an Fe–S melt at 4 GPa and 1450–1500°C with different sulfur contents (10–25 wt %). It was found that with an increase in sulfur content in the iron melt, the degree of diamond dissolution sharply decreases. The stationary (final)
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Index Minerals of the Hydrothermal Arsenide Process of the Formation of Cobalt Deposits of the Bou Offro–El Graara Ore Belt in the Anti-Atlas Province, Morocco Geol. Ore Deposits (IF 0.74) Pub Date : 2021-01-30 V. I. Lebedev, Yu. A. Kalinin
Abstract The distribution of index minerals of the hydrothermal arsenide process of the formation of Ni‒Co–As (±U–Ag), Co–S–As (±Au–W), and Cu–Co–As (±Sb–Ag) quartz–carbonate veins of deposits of the Bou Offro–El Graara ore belt (Morocco) are discussed. The Co arsenide objects of the Bou Azzer ore cluster with typical low-temperature Ni–Co–As (U–Ag) deposits of the five-element hydrothermal type are
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On the Prospects of Diamond Content of the Southern Side of the Vilyui Syneclise Geol. Ore Deposits (IF 0.74) Pub Date : 2021-01-30 V. P. Afanasiev, N. P. Pohilenko, S. S. Kuligin, D. A. Samdanov
Abstract—The paper describes indicator minerals of kimberlites found on the southern side of the Vilyui syneclise in the Markha River basin, a tributary of the Lena River. It is shown that indicator minerals—pyrope and picroilmenite—derive from Middle Paleozoic kimberlites, very likely diamondiferous. Methods are proposed for further studies on determining the prospects for the diamond content of the
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Mineralogy of Precious Metals in Ores of the Biksizak Base–Metal Deposit, South Urals, Russia Geol. Ore Deposits (IF 0.74) Pub Date : 2021-01-30 O. Yu. Plotinskaya, K. A. Novoselov, R. Seltmann
Abstract Gold and silver mineralogy is studied in ores of the Biksizak base-metal deposit (South Urals, Russia). This is a skarn-related carbonate replacement mineralization typical for marginal zones of porphyry-epithermal systems. The variability of precious metals minerals is established. Native gold (fineness 853 to 939) in assemblage with chalcopyrite and sphalerite is the most abundant. A telluride
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Multi-Stage Fluid System Responsible for Ore Deposition in the Ossa-Morena Zone (Portugal): Constraints in Cu-Ore Deposits Formation Geol. Ore Deposits (IF 0.74) Pub Date : 2021-01-30 M. Maia, N. Moreira, S. Vicente, J. Mirão, F. Noronha, P. Nogueira
Abstract The Mociços Cu-deposit is part of a cluster of ancient copper mines in the Sousel-Barrancos metallogenic belt in the Ossa-Morena Zone at the SW Iberia. The orebodies develop along NNW-SSE quartz-carbonate-sulfides veins with pyrite and chalcopyrite as the main sulfide phases, and ore emplacement has been attributed to copper remobilization from the metasedimentary host-rocks, though no detailed
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The Dudica Epithermal Cu–Au Deposit (Republic of North Macedonia) Geol. Ore Deposits (IF 0.74) Pub Date : 2020-11-10 G. Tasev, D. Serafimovski, A. V. Volkov, B. Boev, T. Djordjevic, U. Kolitsch, T. Serafimovski
Abstract— The Dudica deposit is located in the southern part of the Republic of North Macedonia (RNM), not far from the border with Greece in the Kozuf–Aridean volcanic region. The deposit is genetically associated with the Neogene igneous event (≥6 Ma, K/Ar), which is manifested at the intersection of northeast trending faults with the northwest trending Vardar fault zone. The REE spectrum of volcanic
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Sulfur Isotope Fractionation During Sulfide Generation in the Hydrothermal Submarine Systems: The Case of Logatchev, Krasnov, and Rainbow Hydrothermal Fields, Mid-Atlantic Ridge Geol. Ore Deposits (IF 0.74) Pub Date : 2020-11-10 E. O. Dubinina, N. S. Bortnikov, O. O. Stavrova, S. A. Kossova
Abstract— The sulfur isotope composition of single sulfide grains has been studied taking into account their paragenetic sequence in the samples collected from three hydrothermal fields (Logatchev, Krasnov, and Rainbow), located in the northern part of the Mid-Atlantic Ridge. The δ34S values of sulfides are +3.9 to +6, +7.1 to +9.8, and +2.1 to +8.4 ‰ in the Logatchev, Krasnov, and Rainbow fields,
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Research of the Uranium, Niobium, and Tantalum Behavior in the Granite Melt–Chloride Fluid System at 750°C and 1000 Bar Geol. Ore Deposits (IF 0.74) Pub Date : 2020-11-10 A. F. Redkin, V. I. Velichkin
Abstract— The major objective of the study investigation was to find the physicochemical conditions for U, Nb, and Ta mobilization into the solution from acidic melts similar in composition to rhyolitic inclusions in quartz at the unique Streltsovka Mo–U field (Eastern Transbaikalia). The experiments were performed with model homogeneous leucogranite glass (wt %): 72.18 SiO2, 12.19 Al2O3, 1.02 FeO
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Formation Environments of Metasomatites and Ores of the Epithermal Gold–silver Deposits Geol. Ore Deposits (IF 0.74) Pub Date : 2020-11-10 I. N. Kigai
Abstract Preore metasomatites of epithermal gold–silver deposits are formed by various types of hydrothermal solutions—from highly acidic and oxidized (argillization, alunitization, secondary quartzites) and moderately acid (sericitization) to rather reduced and alkaline (adularia). The possible processes creating highly acid mineralizing fluids at shallow depths are: (a) the condensation of the acid
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Evolution of the Vagran Gold-Bearing Placer Cluster (Northern Urals) and Prospects for Revealing Bedrock Mineralization Geol. Ore Deposits (IF 0.74) Pub Date : 2020-11-10 A. V. Lalomov, V. A. Naumov, A. V. Grigorieva, L. O. Magazina
Abstract—More than 10 t of gold have been mined within the Vagran placer cluster (Northern Urals), and the identified primary sources are limited to single noneconomic ore occurrences. Our research has established the heterogeneity of placer gold, which reflects the multistage history of the cluster’s development and the diversity of bedrock mineralization owing to which placer deposits were formed
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Gold and Silver Minerals in Sulfide Ore Geol. Ore Deposits (IF 0.74) Pub Date : 2020-11-10 G. A. Palyanova
Abstract—Gold and silver are capable of forming stable natural compounds with different elements. For gold 36 minerals are known: 10 in the class “Native metals, intermetallic compounds” and 26 in the class “Sulfides (selenides, tellurides, arsenides, antimonides, bismuthides).” For silver, 194 minerals are registered in the MMA, presented in 8 classes. Compared to gold in the class “Native metals
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Seismogenic Nature of Fluid-Dynamic Structural Parageneses of the Uryakh Gold Ore Field (Northeastern Transbaikalia) Geol. Ore Deposits (IF 0.74) Pub Date : 2020-09-22 T. M. Zlobina, V. A. Petrov, V. Yu. Prokofiev, S. S. Abramov, A. A. Kotov, A. A. Wolfson, A. B. Leksin
Abstract New data on the geological structure and ore-bearing structural parageneses of the Uryakh gold ore field are presented. The formation of the deposit occurred in dynamic shear regime along ore-controlling deep-seated faults of the Syulban fault system and faults of the system transverse to it. The interaction of two duplex shear systems resulted in the block structure of the ore field. Tectonophysical
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The Varvarinskoye Complex Copper–Gold Deposit in Northern Kazakhstan: Mineral Types and Ore Composition Geol. Ore Deposits (IF 0.74) Pub Date : 2020-09-22 A. A. Antonenko, N. M. Zhukov, Z. N. Pavlova, T. V. Goikolova
Abstract The Varvarinskoye copper–gold deposit, large in terms of Au and small in terms of Cu, was discovered in 1979 in the western part of the Torgai trough in Kazakhstan. It is composed of Devonian volcanosedimentary and intrusive rocks. Ore zones with a thickness from a few meters to a few tens of meters have been identified against a background of disseminated ore mineralization. They are composed
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Ore-Forming Fluids of the Aleksandrovskoe and Davenda Deposits (Eastern Transbaikalia) Geol. Ore Deposits (IF 0.74) Pub Date : 2020-09-22 A. A. Borovikov, Yu. A. Kalinin, B. N. Abramov, V. P. Sukhorukov
Abstract A study of the composition of fluid inclusions in ore minerals of the Davenda Mo–porphyry deposit and the Aleksandrovskoe sulfide–quartz–gold ore deposit, as well as of fluid inclusions in minerals of igneous rocks, showed that ore-forming fluids inherit the salt and gas composition of magmatic fluids generated during crystallization of ore-bearing rocks of the Amudzhikan–Sretensky Igneous
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Ruby Mineralization in Murzinka–Adui Metamorphic Complex, Central Urals Geol. Ore Deposits (IF 0.74) Pub Date : 2020-09-22 A. Yu. Kisin, V. V. Murzin, A. V. Tomilina, V. N. Smirnov, M. E. Pritchin
Abstract The Lipovka and Alabashka ruby occurrences in the Central Urals hosted in marble of the Murzinka–Adui Anticlinorium are considered. The field works were carried out; the chemical compositions of rocks and minerals and oxygen isotopic composition of corundum and silicates were determined; and micas were dated by the K–Ar method. These occurrences are similar in geological environment and mineral
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Askold Gold Deposit (Askold Island, Primorye, Russia): Physicochemical Parameters and Composition of Ore-Forming Fluids Geol. Ore Deposits (IF 0.74) Pub Date : 2020-07-27 O. O. Stavrova; V. Yu. Prokofiev; A. V. Mokhov; N. S. Bortnikov
AbstractIndividual fluid inclusions in quartz from ore veins of the Askold gold deposit, which was previously attributed to the epithermal type, are studied for the first time. It is established that gold mineralization of Askold Island derived from ore-forming fluids of carbon dioxide–water–salt composition, with a salt concentration of 2.8–4.1 wt % NaCl equiv and a high carbon dioxide concentration
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Oscillatory Zoning in Tennantite-(Fe) at the Darasun Gold Deposit (Eastern Transbaikal Region, Russia) Geol. Ore Deposits (IF 0.74) Pub Date : 2020-07-27 N. G. Lyubimtseva; N. S. Bortnikov; S. E. Borisovskii
AbstractOscillatory zoning in tennantite-(Fe) crystals found in carbonate–sulfide aggregates at the Darasun gold deposit has been studied. Similar elements have been distinguished in zoned crystals: core, “identical oscillatory rhythm,” rhythms with crystallographic and wavy oscillatory zoning, and rim with poorly defined fine oscillatory zoning. Oscillatory zoning is due to considerable variations
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Behavior of Trace Elements during Oxidation of Sphalerite of the Irinovskoe Hydrothermal Sulfide Field (13°20′ N, Mid-Atlantic Ridge) Geol. Ore Deposits (IF 0.74) Pub Date : 2020-07-27 I. Yu. Melekestseva; V. V. Maslennikov; N. R. Ayupova; E. V. Belogub; S. P. Maslennikova; V. E. Bel’tenev; L. Danyushevsky; R. Large
Abstract—The formation of present-day seafloor sulfide deposits is accompanied by their continuous oxidation and crystallization of insoluble Fe oxyhydroxides, which absorb metals (including heavy metals) (Fallon et al., 2017). Due to the high sorption ability of Fe oxyhydroxides, it is suggested that the removal of metals during submarine oxidation into ambient seawater is insignificant (Fallon et
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Gold-Bearing Rodingites of the Agardag Ultramafic Massif (South Tuva, Russia) and Problems of Their Genesis Geol. Ore Deposits (IF 0.74) Pub Date : 2020-07-27 V. V. Murzin; G. A. Palyanova; D. A. Varlamov; S. N. Shanina
Abstract—The limited literature data on gold-bearing albite–pyroxene rodingites are summarized for the Agardag ultramafic massif in southern Tuva. These data are supplemented by new mineralogical, geochemical, thermobarogeochemical, and isotopic–geochemical results in order to reveal the physicochemical mineral formation conditions and sources of ore matter and fluids on gold deposition in rodingites
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The Tumannoe Gold–Antimony Occurrence (East Sayan, Russia): Mineralogy, Fluid Inclusions, S and O Isotopes, and U–Pb and 40 Ar/ 39 Ar Age Geol. Ore Deposits (IF 0.74) Pub Date : 2020-07-27 B. B. Damdinov; L. B. Damdinova; V. B. Khubanov; D. S. Yudin; A.V. Travin; M. D. Buyantuev
AbstractThe article discusses the features of the composition, age, and genesis of gold–antimony mineralization of the East Sayan based on the example of the largest Tumannoe ore occurrence. It is shown that objects of this type are rare in the considered region. In the course of studies, it was found that stibnite, pyrite, and arsenopyrite predominate in ores; Bi minerals (tetradymite, cobaltite,
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Valunistoe Epithermal Au–Ag Deposit (East Chukotka, Russia): Geological Structure, Mineralogical–Geochemical Peculiarities and Mineralization Conditions Geol. Ore Deposits (IF 0.74) Pub Date : 2020-05-15 A. V. Volkov; V. Yu. Prokof’ev; S. F. Vinokurov; O. V. Andreeva; G. D. Kiseleva; A. L. Galyamov; K. Yu. Murashov; N. V. Sidorova
AbstractThe Valunistoe Au–Ag deposit is the third largest among epithermal deposits in Chukotka after the Kupol and Dvoinoe. It is located at the western closing of the East Chukotka flank zone of the Okhotsk-Chukotka volcanic belt. Volcanic domes (Pravogornenskaya, Zhil’ninskaya, Shakhskaya, Valunistaya, Shalaya, and Oranzhevaya, each is 3–6 km in diameter) have the main ore-controlling significance
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Geochemical Characteristics of Volcanogenic Deposits and Exhalation Mineralization in the Crater Part of the Active Kudryavy Volcano (Iturup Island of the Kuril Arc) Geol. Ore Deposits (IF 0.74) Pub Date : 2020-05-15 A. G. Marchenko; A. A. Volfson; M. V. Morozov; N. S. Khrol; G. S. Steinberg; M. G. Steinberg
AbstractExhalation ore mineralization is developing in the crater part of the active Kudryavy volcano. Lithogeochemical sampling results have revealed that Re, Au, Ag, As, Bi, Cd, Cu, Ge, In, Mo, Pb, S, Sb, Se, Sn, Te, Tl, W, Zn, Rb, and Cs accumulate in solid fumarole formations. These elements are transported by high-temperature volcanic gases and are deposited in mineral phases in the near-surface
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Variability of Alunite Quartzite Composition as a Reflection of the Characteristics of Its Genesis Geol. Ore Deposits (IF 0.74) Pub Date : 2020-05-15 A. Z. Vdovets
AbstractBased on 5000 analyses of geological prospecting samples from four alunite deposits (Began’, Ukraine; Haft Sanduq, Iran; Bolshaya Kremenyukha and Kachar, Kazakhstan) and 6000 microprobe analyses of alunite, the features of changes in three parameters of alunite quartzite composition have been studied: (1) alunite content, (2) mole fraction of K in alunite, and (3) correspondence of the amount
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The World’s Largest Fouta Djallon–Mandingo Bauxite Province (West Africa): Part I. Background Geol. Ore Deposits (IF 0.74) Pub Date : 2020-05-15 V. I. Mamedov; A. A. Chausov; E. A. Okonov; M. A. Makarova; N. M. Boeva
Abstract—The recognition of the Fouta Djallon–Mandingo territory as an independent bauxite province is substantiated. It is confined to the morphostructure of the same name within a single geotectonic structure, the sedimentary cover of the Sahara Platform, in the tropical monsoon climate zone in West Africa. The bauxite exploration history, reserve and resource estimates, and production dynamics in
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Comparison of Supercontinent Cycles in the Metallogeny of Niobium Geol. Ore Deposits (IF 0.74) Pub Date : 2020-03-31 A. V. Tkachev; D. V. Rundqvist; N. A. Vishnevskaya
AbstractThe distributions of niobium mineral deposits and their resources on the geological time scale are analyzed. The sampling list includes 45 mineral deposits with their individual resources estimated not less than 105 tons of Nb2О5. The classification of deposits used includes three types, namely, alkaligranitic, foidic, and carbonatitic. The geohistorical variability in niobium metallogeny is
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The Northern Kazakhstan Uranium Province, Kokchetav Massif: U–Pb (ID-TIMS) and Rb–Sr Geochronology of Rocks of Ore-Hosting Volcanotectonic Depressions Geol. Ore Deposits (IF 0.74) Pub Date : 2020-03-31 V. N. Golubev; K. N. Shatagin; E. B. Sal’nikova; I. V. Chernyshev
Abstract—Geochronological studies have been conducted for ore-hosting rocks (quartz rhyolites, felsitic rhyolites, porphyry granites) of some U deposits of the Yakshi-Yangistau complex within the Balkashino ore center of the Northern Kazakhstan uranium province. According to geological maps of various scales, the rocks were traditionally ascribed to the Early–Middle Devonian (quartz and felsitic rhyolites)
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Reduced-Type Alterations at Exogenic Infiltration Uranium Deposits and Their Relation to Rising Groundwater Geol. Ore Deposits (IF 0.74) Pub Date : 2020-03-31 B. T. Kochkin
Abstract—This paper considers examples of “hydrogenic” commercial uranium deposits termed as “sandstone-hosted” in the English literature and characterized by so-called “reduced-type alterations.” In addition to the case when they are absent at the deposit, a few characteristic alterations are identified in different ratios, such as rock bleaching, iron redistribution, argillization, carbonatization
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Mineral System of the Streltsovka Caldera Uranium Deposits (East Transbaikalia) Geol. Ore Deposits (IF 0.74) Pub Date : 2020-03-31 A. A. Pek; V. I. Malkovsky; V. A. Petrov
Abstract—Various hypotheses, including alternative ones, have been put forward in the literature about the sources of ore substance and ore-forming fluids in the deposits of the Streltsovka ore field, which hosts the world’s largest uranium reserves, in excess of 250 000 t U: (1) uranium transport by ascending flow of ore-forming fluids that have separated from a deep subcrustal or intracrustal uranium-bearing
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Mesozoic Acid Magmatites of Southeastern Transbaikalia: Petrogeochemistry and Relationship with Metasomatism and Ore Formation Geol. Ore Deposits (IF 0.74) Pub Date : 2020-03-31 O. V. Andreeva; V. A. Petrov; V. V. Poluektov
Abstract—The characteristic features of the manifestations of acid magmatism and metasomatic hydrothermal alteration processes in Southeastern Transbaikalia, an important mining region in Russia, are discussed. The zoned or beltlike distribution of the ores of various metals, uranium in particular, and other mineral deposits is due to the general evolutionary trends of the geodynamic regimes of the
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Gold Deposits in the Earth’s History Geol. Ore Deposits (IF 0.74) Pub Date : 2020-02-05 N. A. Goryachev
Abstract—The distribution of major gold deposits in the Earth’s history is discussed. The primary heterogeneity of the Archean crust in terms of gold mineralization is demonstrated. Characteristics of the main auriferous metallogenic epochs are given. The predominant associations of the orogenic gold deposits with volcanogenic massive sulfide and copper–nickel deposits during the early periods of the
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Global Metallogeny of Tantalum Through Geological Time Geol. Ore Deposits (IF 0.74) Pub Date : 2020-02-05 A. V. Tkachev; D. V. Rundqvist; N. A. Vishnevskaya
AbstractThe global distribution of tantalum deposits and their resources on the geological time scale is analyzed. The analysis is based on the data for 65 deposits of the world with a resource estimate from 2000 t of Ta2O5, which are classified into five types: pegmatitic, granitic, alkaligranitic, foidic, and carbonatitic. Placers and ore-bearing weathering crusts are taken into account with their
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Coupled Dissolution–Precipitation Reactions of Tennantite–Tetrahedrite Minerals in the Darasun Gold Deposit (Eastern Transbaikalia, Russia) Geol. Ore Deposits (IF 0.74) Pub Date : 2020-02-05 N. G. Lyubimtseva; N. S. Bortnikov; S. E. Borisovsky; O. V. Vikent’eva; V. Yu. Prokofiev
AbstractHeterogeneous rhythmic–zonal aggregates of tennantite-IV partly or completely replacing early homogeneous Zn-tetrahedrite-I grains and euhedral (Fe–Zn)-tennantite-I crystal were found in ores of the Darasun gold deposit. The different stages of fahlore replacement were observed. This initiates at grain boundaries and is terminated by a complete transformation into pseudomorphic, newly formed
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A New Model of a Unique Schlema-Alberoda Five-Element Deposit, Federal Republic of Germany Geol. Ore Deposits (IF 0.74) Pub Date : 2020-02-05 G. B. Naumov; B. P. Vlasov; O. F. Mironova
Abstract—The paper completes a series of works about the unique Schlema-Alberoda deposit. The data on sources of vein and ore minerals and their relation to the processes of regressive alteration of rocks from the contact metamorphism zone are refined. The correlation between stages of mineral formation and their directed change are shown. A general scheme for the sequences in formation stages of the
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Scheelite of the Bystrinskoe Skarn-Porphyry Cu–Au–Fe Deposit, Eastern Transbaikal Region, Russia: Genetic Implications Geol. Ore Deposits (IF 0.74) Pub Date : 2020-02-05 V. A. Kovalenker; O. Yu. Plotinskaya; G. D. Kiseleva; E. A. Minervina; S. E. Borisovskii; O. M. Zhilicheva; Yu. I. Yazykova
Abstract—The first results of optical microscopy, cathodoluminescence (CL), ultraviolet fluorescence (UV), electron-probe microanalysis (EPMA), and laser-ablation inductively-coupled plasma-mass spectrometry (LA-ICPMS) study of scheelite from quartz–molybdenite and quartz–carbonate–sulfide veins and veinlets (porphyry type), as well as the magnetite–sulfide massive, veinlets, and disseminated (skarn
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Isotopic-Geochemical Systematics (Sm–Nd, Lu–Hf) of Neoarchean Subalkaline and Alkaline Rocks of the Keivy Structure (Kola Peninsula): Their Age and Genetic Relations Geol. Ore Deposits (IF 0.74) Pub Date : 2020-02-05 V. R. Vetrin
AbstractThe Neoarchean subalkaline magmatism of the Keivy structure is expressed in the formation of the volcanoplutonic latite–monzonite–granite association (LMGA). The formation of LMGA magmas is assumed to occur due to melting of metasomatically altered mafic rocks during intrusion into the lower crust of basaltic melts initial for rocks of the dike complex and gabbro–labradorite massifs. The alkaline
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Comparison of Diamonds from the Rassolninskaya Depression and Modern Alluvial Placers of the Krasnovishersky District (Ural Region) Geol. Ore Deposits (IF 0.74) Pub Date : 2020-02-05 E. A. Vasilev; I. V. Klepikov; L. I. Lukianova
AbstractThree hundred thirty-six diamonds from deposits of the Rassolninskaya depression and 144 crystals from recent alluvial placers of the Krasnovishersky district were studied by IR absorption and photoluminescence spectroscopy. It is shown that crystals from the Rassolninskaya depression have a close-to-normal distribution for the nitrogen concentration. The average nitrogen content is 725 ppm
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Spinel- and Högbomite-Supergroup Minerals from Sulfide-Free Endogenic Pb–Zn–Sb–As Assemblage in the Pelagonian Massif, Republic of North Macedonia Geol. Ore Deposits (IF 0.74) Pub Date : 2020-02-05 V. N. Ermolaeva; D. A. Varlamov; S. Jančev; N. V. Chukanov
AbstractSulfide-free mineral assemblages with the chalcophile element minerals from occurrences associated with altered rocks of Pelagonian massif, Republic of North Macedonia have been studied. The inputting sequence of various ore-forming constituents has been revealed on the basis of morphological features, zoning of the spinel-group minerals, and the högbomite supergroup minerals. Conclusions about
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New Data on Chemical Composition and Vibrational Spectra of Magnetoplumbite-Group Minerals Geol. Ore Deposits (IF 0.74) Pub Date : 2020-02-05 N. V. Chukanov; S. S. Vorobei; V. N. Ermolaeva; D. A. Varlamov; P. Y. Plechov; S. Jančev; A. V. Bovkun
AbstractMagnetoplumbite-group minerals from various paragenetic assemblages, including a xenolith of altered garnet lherzolite from the Obnazhennaya kimberlite pipe in Yakutia, sulfide-free metasomatic Pb–Zn–Sb ore from the Pelagonian massif in the Republic of North Macedonia, and some other metasomatic occurrences have been studied with electron microprobe, as well as using IR and Raman spectroscopy
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