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Shvedov, Gennadiy, Pavel Samorodsky, Vladimir Makarov, Egor Muromtsev, Maksim Shadchin, Boris Lobastov e Yuri Glushkov. "Arsenical native copper from Au-Cu porphyry Ak-Sug deposit, Eastern Tyva". Ores and metals, n.º 1 (21 de maio de 2021): 77–92. http://dx.doi.org/10.47765/0869-5997-2021-10005.
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The geology of the Ak-Sug Au-Cu-porphyry deposit in the eastern Tyva is considered. The distribution of native copper in ores of the deposits was studied. It has been established that the native copper is of both hypogene and supergene origin. The hypogene native copper is characterized by an elevated arsenic content (up to 4.4 %) and occurs in association with copper arsenides, native silver, zircon, brannerite, xenotime-(Y), florensite-(Ce), chalcocite, and berzelianite. Hypogene native copper is confined to ore schistosity zones .
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Lien, Nguyen Thi, e Nguyen Van Pho. "Formation of secondary nonsulfide zinc ore in Cho Dien Pb-Zn deposits". VIETNAM JOURNAL OF EARTH SCIENCES 40, n.º 3 (4 de junho de 2018): 228–39. http://dx.doi.org/10.15625/0866-7187/40/3/12615.
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In Viet Nam, non-sulfide zinc ore in the Cho Dien deposit has been exploited for a long time. Up to the present, zinc ore remains the major exploited ore in Cho Dien. There are numerous studies of Pb-Zn ore in Cho Dien. However, most of the studies have dedicated only to description of mineralogical and chemical composition of Pb-Zn ore. There has been no publication on this non-sulfide zinc ore. Based on the mineralogical studies, the content of Pb and Zn in groundwater determined by reflective microscope, SEM, EPMA and ICP-MS methods, the study explained the formation of secondary non-sulfide zinc ore in the Cho Dien deposit. Strong weathering process makes the upper part of ore bodies completely oxidized. Difference in geochemical behavior of lead (Pb) and zinc (Zn) in the oxidation process of Pb-Zn ore is the reason to form non-sulfide zinc ore in the Cho Dien deposit. Oxidation of primary Pb-Zn ore is mainly sphalerite, pyrite, galena minerals which creates a low pH environment and transforms of zinc from immobile (sphalerite - ZnS) to mobile (Zn2+) and retained in solution under acid pH conditions whereas lead has the tendency to form soluble minerals (anglesite, cerussite). The acid neutralization actions of the surrounding rocks make zinc precipitate, to form secondary non-sulfide zinc minerals.ReferencesAndreas Nuspl, 2009. Genesis of nonsulfide zinc deposits and their future utilization (www.geo.tu-frei berg.de/oberseminar/OS_09/Andreas_Nuspl.pdf.Boland M.B., et al., 2003. The Shaimerden supergene zinc deposit, Kazakhstan: Economic Geology, 98(4), 787-795.Chau N.D., Jadwiga P., Adam P., D.V. Hao, L.K. Phon, J. Paweł, 2017. General characteristics of rare earth and radioactive elements in Dong Pao deposit, Lai Chau, Vietnam, Vietnam J. Earth Sci., 39(1), 14-26.Dao Thai Bac, 2012. Characteristics and distribution law of lead-zinc metallogenic fomations in Viet Bac region. Doctoral thesis.Heyl A.V., Bozion C.N., 1962. Oxidized zinc deposits of the United States, Part 1. General Geology: U.S. Geological Survey Bulletin 1135-A.Hoa T.T., et al., 2010. By-products in lead-zinc and copper ores of Northeast Vietnam. J. Sci. of the Earth, 289-298 (in Vietnamese).Hoang Minh Thao, Tran Thi Hien, Dao Duy Anh, Pham Thi Nga, 2017. Mineralogical characteristics of graphite ore from Bao Ha deposit, Lao Cai Province and proposing a wise use. Vietnam J. Earth Sci., 39(4), 324-336.Jurjovec J., et al., 2002. Acid neutralization mechanisms and metal release in mine tailings: A laboratory column experiment: Geochimica et Cosmochimica Acta, 66, 1511-1523.Large D., 2001. The geology of non-sulphide zinc Deposits - an Overview: Erzmetall, 54(5), 264-276.Maria Boni, 2003. Nonsulfide Zinc Deposits: a new - (old) type of economic mineralization. Society for geology applied to mineral deposits (SGA) News, Number 15. https://www.e-sga.org/fileadmin/sga/newsletter/news15/art01.html.McPhail D.C., et al., 2003, The geochemistry and mobility of zinc in the regolith: in Roach, I.C., ed., Advances in Regolith, 287-291.Murray W. Hitzman, et al., 2003. Classification, genesis, and exploration guides for non-sulfide zinc deposits: Economic Geology, 98(4), 685-714.Nguyen V.P., 2013. Wet tropical wethering in Viet Nam. Natural Science and Technology Publisher.Nicola Mondillo, 2013. Supergene Nonsulfide Zinc-Lead Deposits: The Examples of Jabali (Yemen) and Yanque (Peru). Doctoral thesis.Nordstrom D.K., Alpers C.N., 1999. Geochemistry of acid mine waste. Review in Economic Geology, the environmental geochemistry of ore deposits/Eds. G.S.Plumlee, M.J. Logsdon. Part A: Processes, techniques, and health issues, 6A, 133-160.Reynolds N.A., et al., 2003. The Padaeng Supergene Nonsulfide Zinc Deposit, Mae Sod, Thailand. Economic Geology, 98(4), 773-785.Sangameshwar S.R., Barnes H.L., 1983. Supergene Processes in Zinc-Lead-Silver Sulfide Ores in Carbonates: Economic Geology, 78, 1379-1397.Stumm W., Morgan J.J., 1996. Aquatic Chemistry, Third Edition. John Wiley & Sons, New York, NY.Takahashi T., 1960. Supergene alteration of zinc and lead deposits in limestone: Economic Geology, 55, 1083-1115.Thornber M.R. and Taylor G.F., 1992. The mechanisms of sulphide oxidation and gossan formation, in: Butt, C.R.M., and Zeegers H., (Eds.)., Regolith exploration geochemistry in tropical and subtropical terrains, in Govett G.J.S., ed., Handbook of exploration geochemistry: Amsterdam, Elsevier, 4, 119-138.Tran Trong Hoa, 2005. Potential assessment of By- products in lead-zinc and copper deposits of Northeast Vietnam. Final report.Tran Tuan Anh, 2010. Studying accompanying component in the types of potential deposits of basic metals and precious - rare metals of north Viet Nam to improve the efficiency of mining and environmental protection. Final report. KC.08.24/06-10.Tran Tuan Anh, et al., 2011. Mineralogical and geochemical characteristics and forming conditions of lead - zinc deposits in Lo Gam structure, northern Vietnam. J. Sci. of the Earth, 33(3DB), 393-408 ( in Vietnamese).Vito Coppola et al., 2009. Nonsulfide zinc deposits in the Silesia - Cracow district, Southern Poland. Springer Link, 44, 559-580.Vito Coppola, et al., 2007. Non-sulfide zinc deposits in Upper Silesia, Southern Poland. Proceeding of the Ninth Biennial SGA Meeting, Dublin, 1401-1404.Williams P.A., 1990. Oxide zone geochemistry: Ellis Horwood Ltd., Chichester, UK, 286p.
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Kalinin, Arkadii A., e Nikolay M. Kudryashov. "Porphyry-Related Metamorphosed Au-Ag and Cu-Mo Deposits in the Precambrian of the Fennoscandian Shield". Minerals 11, n.º 2 (29 de janeiro de 2021): 139. http://dx.doi.org/10.3390/min11020139.
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The Pellapahk Cu-Mo and Oleninskoe Au-Ag deposits in the western segment of the Russian Arctic in the Kolmozero–Voronya greenstone belt are considered two parts of an Archean (2.83–2.82 Ga) porphyry-epithermal system, probably the oldest one defined in the Fennoscandian Shield. Formation of the Oleninskoe Au-Ag deposit at the epithermal stage of the system is indicated by the spatial and genetic relationships with the sills of granite porphyry, the geochemical association of ore elements (Au, Ag, Cu, Pb, Sb, As), an Au/Ag ratio of <0.2, and the multiplicity of silver mineralization with different Ag, Cu, Pb, Sb sulfosalts. The geological–structural characteristics of the Oleninskoe and the Pellapahk, i.e., their location in a shear zone, the morphology and size of ore bodies, the scale of the deposits, and the intensity and zoning of rock alteration, do not oppose this model. Mineralized rocks of the Pellapahk Cu-Mo and Oleninskoe Au-Ag deposits were amphibolite metamorphosed in the Neoarchean and again in the Paleoproterozoic. Structures of sulfide melt crystallization formed in the ores during metamorphism, those are fine intergrowths of galena, argentotetrahedrite, pyrargyrite, pyrrhotite, ullmannite, stutzite, and other mineral phases of low-melting-point metals such as Ag, Cu, Pb, Sb, As, Bi.
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Lebedev, V. I., A. A. Borovikov, L. V. Gushchina e I. S. Shabalin. "Physico-chemical modeling of hidrothermal mineralization processes at Ni-Co-As (± U-Ag), Co-S-As (± Au-W), Cu-Co-As (± Sb-Ag) deposits." Геология рудных месторождений 61, n.º 3 (19 de junho de 2019): 31–63. http://dx.doi.org/10.31857/s0016-777061331-63.
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A generalization of the results of the study of the composition of metal-bearing fluids of cobalt deposits of hydrothermal Genesis, formed in different geodynamic settings in connection with the formation of alkaline and alkaline-basite intrusions and dikes. To determine the physical and chemical parameters of ore deposition from fluid inclusions in minerals, both traditional and new instrumental methods of thermobarogeochemistry were used: thermo-and cryometry, RAMAN spectroscopy, concentration of ore and petrogenic elements in individual fluid inclusions were evaluated by LA-ICP-MS. The obtained results served as the basis for the study, the main task of which was the thermodynamic modeling of the conditions of joint transport and deposition of Co, Ni, Cu, Fe, Mg, Ca, Ag, Au, Bi, U, Pt and Pd C calculation of a number of equilibrium States of the hydrothermal system, the composition close to the natural ore-forming fluids. Physical and chemical factors of native deposits-gold, silver, platinum and palladium in the ores of such deposits are revealed. The obtained data can serve as a basis for the development of correct genetic models of ore-forming systems of cobalt deposits and contribute to solving the problems of their search.
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Colomban, Philippe, Burcu Kırmızı e Gulsu Simsek Franci. "Cobalt and Associated Impurities in Blue (and Green) Glass, Glaze and Enamel: Relationships between Raw Materials, Processing, Composition, Phases and International Trade". Minerals 11, n.º 6 (15 de junho de 2021): 633. http://dx.doi.org/10.3390/min11060633.
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Minerals able to colour in blue (and green in combination with yellow pigments) are limited in number and geologically. After presenting a short history of the use of cobalt as a colouring agent of glass, glaze and enamel in the Western/Mediterranean, Islamic and Asian worlds since Antiquity, we will present the different forms (dissolved ions, natural and synthetic crystalline phases/pigments) of cobalt and associated elements regarding primary (transition metals) and secondary geological deposits (transition metals and/or arsenic, bismuth, silver). Attempts to identify the origin of cobalt have been made by many authors considering the associated elements but without considering the important modifications due to different processing of the raw materials (extraction/purification/formulation). We review the information available in the ancient reports and present literature on the use of cobalt, its extraction and production from the ores, the different geological sources and their relationship with associated elements (transition metals, bismuth, arsenic, and silver) and with technological/aesthetic requirements. (Partial) substitution of cobalt with lapis lazuli is also addressed. The relative application of non-invasive mobile Raman and pXRF analytical instruments, to detect mineral phases and elements associated with/replacing cobalt is addressed, with emphasis on Mamluk, Ottoman, Chinese, Vietnamese and Japanese productions. The efficiency of Ni-Zn-As diagram proposed by Gratuze et al. as a classification tool is confirmed but additionally, CoO-Fe2O3−MnO and CoO-NiO-Cr2O3 diagrams are also found as very efficient tools in this research. The relationship between the compositional data obtained from the artefacts and historical questions on the origin and date of their production are discussed in order to obtain a global historical view. The need of a better knowledge of (ancient) deposits of cobalt ores and the evolution of cobalt ore processing with time and place is obvious.
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Diallo, Mamadoudjan, Mohammed Bouabdellah, Gilles Levresse, Johan Yans, Francesca Castorina, Andreas Klügel, Mohamed Mouhagir, Salim El Mouden e Lhou Maacha. "Mineralogy, Fluid Inclusion, and C-O-Sr Isotope Geochemistry to Unravel the Evolution of the Magmatic-Hydrothermal System at the Igoudrane Silver-Rich Deposit (Imiter District, Eastern Anti-Atlas, Morocco)". Minerals 11, n.º 9 (12 de setembro de 2021): 997. http://dx.doi.org/10.3390/min11090997.
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The Igoudrane mine with a total production of 700,000 t of ore grading 485 g/t Ag is currently one of the most productive mines in the Imiter district of the eastern Anti-Atlas in Morocco. The silver-rich ± base metal deposit occurs dominantly as vein- and hydrothermal breccia-hosted orebodies at the interface between the lower Ediacaran turbidites of the Saghro Group and the unconformably overlying, dominantly felsic volcanic, and volcaniclastic rocks of the late Ediacaran Ouarzazate Group. Higher-grade ores are lithologically hosted by the uppermost organic-rich black shale unit and structurally controlled by the intersection of subvertical NW- and NE-trending fault systems. Ore-related hydrothermal alteration includes, in order of decreasing abundance, carbonatization, silicification, sericitization, and chloritization. Three primary paragenetic stages of veining and associated silver ± base metal mineralization have been recognized: (1) early pyrite + quartz + Ag-bearing sulfides and sulfosalts; (2) main Ag-bearing sulfides and sulfosalts + calcite ± fluorite ± dolomite; and (3) late quartz + calcite + base-metal sulfides (galena, sphalerite, pyrite, chalcopyrite). Irrespective of the ore stage, the dominant Ag-bearing ore minerals are Ag-Hg amalgam, argentite, freibergite, acanthite, polybasite, pyrargyrite, and proustite. Fluid inclusion data show a trend of decreasing temperatures with time, from the main silver stage (Th = 180 ± 12 °C) to late base-metal stage (Th = 146 ± 7 °C), consistent with fluid mixing, cooling, and/or dilution. The coexistence of aqueous-rich and vapor-rich fluid inclusions together with variations in bulk salinity (NaCl + CaCl2) of the mineralizing fluids during the main silver stage, at similar temperatures, indicate that boiling and subsequent degassing occurred during the main ore-forming event due to a pressure decrease. Calculated δ18Ofluid values along with REE+Y and Sr isotope constraints suggest that the ore-forming fluids originated from a predominantly magmatic source, although incursion of meteoric waters during collapse of the hydrothermal system could have contributed to deposition. The post-ore, base-metal quartz-carbonate-dominated mineralization was deposited from dilute Ca-Na-Cl-bearing fluids at temperature below 150 °C. Overall, fluid–rock interaction with the black shales along major faults and thin permeable horizons, boiling-degassing—with subsequent fluid mixing, cooling, and/or dilution—were the main mechanisms of silver deposition.
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Makshakov, Artem S., e Raisa G. Kravtsova. "Stream Sediments of the Pestrinsk Silver-Bearing System (Northeastern Russia)". Minerals 11, n.º 1 (11 de janeiro de 2021): 65. http://dx.doi.org/10.3390/min11010065.
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The composition, structure, and formation features of the exogenous anomalous geochemical fields (AGCFs) identified through stream sediments (SSs) are considered here within the Pestrinsk silver-bearing system and the Goltsovy silver-polymetallic deposit. The research was performed in the southern part of the Balygychan-Sugoy trough (northeastern Russia). The exogenous AGCFs of the main indicator elements of ores, formed in cryolithogenesis zone conditions, were studied. We used the results of multi-scale areal geochemical surveys of SSs. A survey of SSs at 1:200,000 scale was found to be effective at the stage of regional forecasting. Indeed, it is characterized by simplicity and the possibility of obtaining information operatively regarding the metallogeny of the area. It was found that at the local forecast stage, when prospecting for mineralization, the most effective was a survey of SSs at 1:50,000 scale. The AGCFs identified during this survey were distinguished by a richer component composition, higher contrast, and closer relationship with ores. During the lithochemical sampling of the watercourse heads, where alluvial sediments were found to be almost completely absent, a positive result was obtained by the bryolithochemical method, which is based on moss sampling together with a fine fraction of alluvium held by a moss cushion. The method enabled the sampling of watercourse heads and thus yielded information about the presence or absence of anomalous concentration fields of ore elements.
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Barton, Paul B. "Ore textures: problems and opportunities". Mineralogical Magazine 55, n.º 380 (setembro de 1991): 303–15. http://dx.doi.org/10.1180/minmag.1991.055.380.02.
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AbstractOver the past several decades, thinking about chemical processes in rocks had been dominated by experimental and theoretical treatments of mineral equilibrium, which is the state from which the time variable has been excluded. But, to an extent exceeding that of any of our sister sciences, we in geology are concerned with the behaviour of things as a function of time; thus equilibrium is but one of several interesting boundary conditions. Textures, (defined as the spatial relations within and among minerals and fluids, regardless of scale or origin) provide a means to sort out and identify successive states. In fact, it is the pattern of evolution of those states that enables us to deduce the processes. We may well draw the analogy with thermodynamics and kinetics, respectively:equilibrium textures and phase assemblages, via thermodynamic analysis → definition of conditions of equilibration,whereaskinetics, as displayed in disequilibrium textures → sequence of events and processes of mineralization.The interpretation of textures is one of the most difficult yet important aspects of the study of rocks and ores, and there are few areas of scientific endeavour that are more subject to misinterpretation. Although the difficulties are many, the opportunites for new understanding are also abundant. Textural interpretations have many facets: some are well established and accepted; some that are accepted may be wrong; others are recognised to be speculative and controversial; and we trust that still other textural features remain to be described and interpreted. This paper will deal principally with low-temperature, epigenetic ore deposits, and will emphasise silica and sphalerite; but extension to other materials is not unreasonable.Ore and gangue minerals react internally, or with their environment, at widely ranging rates, ranging from the almost inert pyrite, arsenopyrite, well-crystallised quartz, and tourmaline to the notoriously fickle copper/iron and copper/silver sulfides. Arrested or incomplete reactions may be identifed by textural criteria and, when appropriately quantified, can provide guides to the duration of geological processes.In recent years so much emphasis has been placed on isotopes, fluids, chemistry, and deposit and process models that the textural features have been ignored. In part this oversight occurs because we have grown accustomed to using superposition, cross-cutting, pseudomorphism, mutual intergrowths, exsolution and so on as off-the-shelf tools, to be grasped and applied without evaluation or even description. Surely science must build on previous work without constant and exhaustive reassessment, but for mineral textures a little reassessment may yield substantial benefit.
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Ratkin, V. V., L. F. Simanenko e O. A. Eliseeva. "Microfacies and Mineral Assemblages of Silver–Base-Metal Ores of the Maiminovskoe Vein Deposit (Sikhote-Alin, Dal’negorsky Ore District)". Russian Journal of Pacific Geology 12, n.º 6 (novembro de 2018): 521–38. http://dx.doi.org/10.1134/s1819714018060052.
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Osmonbetov, E. "Geology and Goldness Deposits Shambesai". Bulletin of Science and Practice 6, n.º 5 (15 de maio de 2020): 249–56. http://dx.doi.org/10.33619/2414-2948/54/31.
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The specificity of the location and the degree of field search are shown. The characteristic of ore zones (bodies), the mineral composition of ores and reserves are given. The deposit is similar to the gold deposits of the Karlinsky type. Two main technological types of ores have been distinguished: easily miscible oxidized ores that do not contain harmful impurities, suitable for heap leaching, and refractory sulfide gold-arsenic ores, requiring special complex processing methods. These ores are planned to be mined together with oxidized and temporarily stored separately. It is necessary to organize a public hearing and involve professional experts in the examination of projects.
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De la Nuez Colon, D., e M. Santa Cruz Pacheco. "Gold and gold-bearing volcanogenic massive sulphide deposits of the Central Cuba". Proceedings of higher educational establishments. Geology and Exploration, n.º 3 (28 de fevereiro de 2021): 27–37. http://dx.doi.org/10.32454/0016-7762-2020-63-3-27-37.
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Background. Volcanogenic massive sulphide deposits (VMS) are the most important sources of Cu and Zn; they account for a large share of the world production of Pb, Ag, Au, Se, Te, Bi and Sb, as well as small amounts of many other metals. The polymetallic VMS deposits of economic value of varying degrees are known in the rocks of the Los Pasos Cretaceous Formation, Cuba.Aim. To show the potential of the Cretaceous volcanic deposits of Central Cuba for gold, silver, copper, zinc and lead deposit prospecting.Materials and methods. The study characterises the San Fernando, Independencia, Antonio, Los Cerros VMS deposits and the Boca del Toro and El Sol ore occurrences located in the Los Pasos Formation. The similarities and differences in the mineral and elemental composition and structures of the ores of these objects are described, which underlie the assessment of their economic importance.Results. The latitudinal zoning of VMS and noble metal mineralisation of the Central Cuban ore region is outlined. In the west, copper-VMS deposits with accompanying gold ore objects prevail. In the east, copper-zinc VMS deposits with barite and gold-silver objects are widespread.Conclusions. It is necessary to assume the different erosional sections corresponding to the blocks of the Cretaceous volcanic arc of Central Cuba, which is larger in the west and smaller in the east. Proceeding from the presence of veinlet gold ores, their confinement to tectonic zones and the lack of correlation between noble and chalcophile metals at the San Fernando deposit, as well as significantly different gold-silver ratios in the considered ore objects, it could be assumed that some of the gold-silver ores were formed after VMS. The obtained Au/Ag ratios are close to the ores of the high sulphidation type (high sulphide ores) from similar ore regions of Venezuela and the Kur-il island arc. In this regard, one can expect hidden gold deposits in the west and gold-silver deposits in the east of the studied area.
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Mikulski, Stanisław Z., Sławomir Oszczepalski, Katarzyna Sadłowska, Andrzej Chmielewski e Rafał Małek. "The occurrence of associated and critical elements in the selected documented Zn-Pb, Cu-Ag, Fe-Ti-V, Mo-Cu-W, Sn, Au-As and Ni deposits in Poland". Biuletyn Państwowego Instytutu Geologicznego 472, n.º 472 (20 de novembro de 2018): 21–52. http://dx.doi.org/10.5604/01.3001.0012.7113.
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As part of the research subject of the Polish Geological Survey, funded by NFOŚiGW, a research project was carried out at PGI-NRI in 2015–2018. Its main task was quantitative and qualitative identification of elements accompanying the main ore and associated elements, including critical ones, and mineralogical identification of their main carriers in metallic ore deposits documented after World War II, representing the main metallogenic formations in Poland. The research focused mainly on drill cores from historical survey boreholes, rarely samples from open-pits and deep mines, representing: Mesozoic Zn-Pb ores, Lower Zechstein Cu-Ag ores, Mesoproterozoic Fe-Ti-V ores, Mo-Cu-W porphyry ores, stratiform Sn ores in the Sudetes, Variscan vein and metasomatic Au-As polymetallic ores, and Cenozoic Ni ores. The PIG-PIB Chemical Laboratory performed analytical work (ICP-MS, WD-XRF, GF-ASS), which allowed quantitative identification of approximately 60 chemical elements. In addition, complementary mineralogical and petrographic studies of the trace element carriers were carried out using a polarizing microscope and an electron microprobe (CAMECA SX-100). Before sampling, metal ore-bearing intervals were examined for the content of chemical elements using a portable spectrometer (Olympus XRF Delta). The results indicate the presence of numerous elements in studied deposits, including those currently regarded as critical for the European Union economy. The collected materials allowed both developing detailed geochemical and mineralogical characteristics of ores from individual deposits and identifying critical elements. They show a clear correlation with the main ore metals, and their resources can be a matter of interest in terms of raw materials.
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Hu, Hao, Jian-Wei Li, Daniel E. Harlov, David R. Lentz, Christopher R. M. McFarlane e Yue-Heng Yang. "A genetic link between iron oxide-apatite and iron skarn mineralization in the Jinniu volcanic basin, Daye district, eastern China: Evidence from magnetite geochemistry and multi-mineral U-Pb geochronology". GSA Bulletin 132, n.º 5-6 (30 de agosto de 2019): 899–917. http://dx.doi.org/10.1130/b35180.1.
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Abstract Various styles of ore deposits may form from a single magmatic-hydrothermal system. Identification of a possible genetic link between different ore types in a region is not only of critical importance for a better understanding of the magmatic-hydrothermal processes, but can also help in successful mineral exploration. Both iron oxide-apatite (IOA) and iron skarn deposits are closely associated with intrusive rocks of intermediate to felsic in composition, but whether these two ore types can form from the same magmatic intrusion remains poorly understood. In this study, we present a comparative study between a newly identified subsurface IOA ore body located at the apex of a diorite porphyry and the iron skarn ore bodies located immediately above it in the Jinniu volcanic basin of the Daye district, Middle-Lower Yangtze River metallogenetic belt (MLYRMB), eastern China in order to highlight a genetic link between these two styles of mineralization. The IOA ores are dominated by Ti-rich magnetite with variable amounts of fluorapatite, diopside, and actinolite. This mineralogical assemblage is distinctly different from the iron skarn ores, which consist mainly of Ti-depleted magnetite and subordinate pre-ore garnet and diopside, and post-ore quartz, chlorite, calcite, and pyrite. In addition, magnetite from the IOA ores is characterized by well-developed ilmenite lamellae and has high concentrations of Ni, V, Co, and Ga, consistent with high temperature crystallization, whereas magnetite grains from the iron skarn ores usually exhibit oscillatory growth zones and contain much lower Ni, V, Co, and Ga, indicating their formation under relatively low temperatures. Titanite and fluorapatite from the IOA ores have U-Pb ages of 132.5 ± 2.4 Ma to 128.4 ± 3.0 Ma, which match a titanite U-Pb age for the associated iron skarn ores (132.3 ± 2.0 Ma), and are consistent with zircon U-Pb ages for the ore-hosting diorite porphyry (130.4 ± 0.7 Ma to 130.3 ± 0.5 Ma). This age consistency supports a possible genetic link among the diorite porphyry, IOA ores, and iron skarn ores. We propose that the IOA and skarn ores are the products of two consecutive mineralization stages of the same magmatic-hydrothermal system, involving a high-temperature, hypersaline fluid coexisting with the diorite porphyry magma during emplacement and a subsequent low temperature, diluted hydrothermal fluid. Other IOA and iron skarn deposits of similar ages (130 Ma) are found in a series of volcanic basins in the MLYRMB, which forms one of the world’s largest IOA metallogenic belts. The close association of the two ore styles identified at Daye provides a useful exploration guide for IOA and iron skarn deposits both on a local and regional scale.
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Necrasov, E. M., e L. A. Dorozhkina. "About the ore conduits at the near-surface deposits of gold-silver ores". Proceedings of higher educational establishments. Geology and Exploration, n.º 1 (28 de fevereiro de 2017): 37–49. http://dx.doi.org/10.32454/0016-7762-2017-1-37-49.
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It is shown that at the rather numerous near-surface gold-silver ore deposits (sometimes with tellurides), developed in the East of Russia, the fractured ore conduits can be revealed. From them, the bundles and a series of vein-veinlet ore bodies or metasomatic gold-bearing rocks start. In both cases the areas with bonanza contents of the noble metals are established. The portion of their stocks sometimes reaches 70% in a total. Exploration drilling along the barren flanks of the ore-conducting channels can identify new ore, hidden in the depth interval from 100-200 to 400 meters or more, and replenish stocks of the deposits.
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PATERSON, COLIN J. "Ore Deposits of Gold and Silver". Mineral Processing and Extractive Metallurgy Review 6, n.º 1-4 (janeiro de 1990): 43–66. http://dx.doi.org/10.1080/08827509008952656.
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Novoselov, Konstantin, Elena Belogub, Ekaterina Palenova e Ivan Blinov. "Silver minerals in the Unkur sandstone-hosted Cu deposit (Transbaikalia region, Russia)". Neues Jahrbuch für Mineralogie - Abhandlungen Journal of Mineralogy and Geochemistry 196, n.º 3 (1 de julho de 2020): 221–30. http://dx.doi.org/10.1127/njma/2020/0192.
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The Kodar-Udokan ore district in the Transbaikalia region of Russia contains numerous sandstone-hosted Cu deposits and occurrences with variable Ag content. The Unkur deposit with possible resources of 62 million tonnes at 0.53 % Cu and 38.6 g/t Ag is hosted in metasedimentary rocks of the Udokan Group of 2.2–2.6 Ga in age. The bornite–chalcopyrite ores from the deposit are characterized by disseminated, lenticular, pocket, and veinlet textures and also contain numerous silver minerals including native silver, mercurian silver (up to 37.4 wt% Hg), stromeyerite, mckinstryite, balkanite, and naumannite. Isomorphic silver is also hosted in bornite (up to 3.8 wt%) and chalcocite (up to 1.8 wt% Ag). The microscopic relationships between ore minerals and stability of stromeyerite indicate almost synchronous formation of native silver, mercurian silver, and stromeyerite at a temperature of < 100 °C. The presence of Ag–Hg minerals is a characteristic feature of ores from the Cu–Ag deposits hosted in sedimentary and carbonate-sedimentary rocks.
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MELNIKOV, ANTON VLADIMIROVICH, VITALY ALEKSEEVICH STEPANOV e DMITRIY VALERYEVICH YUSUPOV. "DISCOVERY AND STUDY HISTORY POKROVSKY GOLD ORE DEPOSIT IN THE AMUR REGION". Messenger AmSU, n.º 91 (2020): 63–72. http://dx.doi.org/10.22250/jasu.11.
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A brief history of the discovery and study of the large Pokrovsky gold ore deposit of the Amur Region, from the ores of which about 63 tons of gold were extracted, is given. The role of scientific and production organizations and individual geologists in the discovery of the deposit is shown. According to the results of almost half a century of research, the deposit is classified as a near-surface gold-silver formation with a typical composition of ores, near-ore metasomatites and native gold for deposits of this type. The closest analogue of Pokrovka is the Kubak deposit of the Omolonsky gold-silver province.
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Su, Zhi-Kun, Xin-Fu Zhao, Xiao-Chun Li, Mei-Fu Zhou, Allen K. Kennedy, Jian-Wei Zi, Carl Spandler e Yue-Heng Yang. "UNRAVELING MINERALIZATION AND MULTISTAGE HYDROTHERMAL OVERPRINTING HISTORIES BY INTEGRATED IN SITU U-Pb AND Sm-Nd ISOTOPES IN A PALEOPROTEROZOIC BRECCIA-HOSTED IOCG DEPOSIT, SW CHINA". Economic Geology 116, n.º 7 (1 de novembro de 2021): 1687–710. http://dx.doi.org/10.5382/econgeo.4840.
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Abstract Precambrian iron oxide copper-gold (IOCG) deposits are generally encountered with multistage hydrothermal overprints and hence have complex isotopic records. Precise dating of ore-forming and overprinting events and assessment of time-resolved metal sources are fundamental for understanding ore genesis. Here, we quantify the evolution history by integrating in situ U-Pb dating of texturally constrained allanite and Sm-Nd isotope data of ores and major rare earth element (REE) minerals in the breccia-hosted Lanniping Fe-Cu deposit in Kangdian region, southwestern China. The economically mineralized breccia in Lanniping Fe-Cu deposit is characterized by pervasive and texturally destructive replacement of polymictic clasts, including host metasedimentary packages, the intruded dolerite, and pre-ore halokinetic breccia. Ore minerals in cements are mainly composed of magnetite, chalcopyrite, bornite, and variable amounts of REE-rich minerals (e.g., apatite and allanite/epidote). Two types of allanite were identified in ores. Type I prismatic allanite texturally intergrown with magnetite has a SHRIMP U-Pb age of 1728 ± 20 Ma (1σ), which matches a zircon U-Pb age of 1713 ± 14 Ma (2σ) for the dolerite clasts and provides the direct age constraint on the Fe-Cu mineralization event. Type II anhedral allanite shows complex zoning and is spatially associated with, but texturally later than, magnetite, apatite, and chalcopyrite. This type of allanite yields significantly younger SHRIMP dates of 1015 ± 33 (1σ) and 800 ± 16 Ma (1σ) for cores and rims, respectively, which correspond to discrete regional magmatic events and hence record hydrothermal overprint/remobilization events of ore minerals in the deposit. Integrated Sm-Nd isotope compositions of type I allanite, apatite, and whole ores generally align along the reference Sm-Nd isochron of 1728 Ma, further confirming the primary ore formation at ~1.7 Ga. Corresponding εNd(1728 Ma) values ranging from –2.8 to 0.3 are significantly higher than those of the host metasedimentary rocks (–9.5 to –6.2) but comparable to those of contemporaneous igneous intrusions (–0.3 to 5.3) in the region, demonstrating that REE components of the primary ores were dominantly sourced from rocks of mantle-derived affinity. Both cores and rims of the younger type II allanite grains have Nd isotope compositions consistent with the unique time-evolved line of the ~1.7 Ga ores, implying that REEs incorporated into type II allanite were ultimately sourced from the primary ores in this deposit. The combined texture, chemical, U-Pb, and Sm-Nd isotope data thus demonstrate that REE remobilization was localized during post-ore hydrothermal overprint with negligible external inputs of REEs to the primary ores in the Lanniping deposit. In this contribution, we not only date primary ore formation but also recognize several younger allanite generations that record internal metal redistributions in response to post-ore tectonothermal events. Our study highlights the potential of ore-associated REE minerals such as allanite for resolving the age of multiple stages of hydrothermal events in complex ore deposits by ion probe, provided that careful examination of textural and paragenetic relationship of ores is conducted. Our finding of these younger allanite generations also exemplifies the significance of evaluation on time-resolved metal input for better characterizing the evolution history of the IOCG deposits.
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Damdinova, Ludmila, e Bulat Damdinov. "Tungsten Ores of the Dzhida W-Mo Ore Field (Southwestern Transbaikalia, Russia): Mineral Composition and Physical-Chemical Conditions of Formation". Minerals 11, n.º 7 (5 de julho de 2021): 725. http://dx.doi.org/10.3390/min11070725.
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This article discusses the peculiarities of mineral composition and a fluid inclusions (FIs further in the text) study of the Kholtoson W and Inkur W deposits located within the Dzhida W-Mo ore field (Southwestern Transbaikalia, Russia). The Mo mineralization spatially coincides with the apical part of the Pervomaisky stock (Pervomaisky deposit), and the W mineralization forms numerous quartz veins in the western part of the ore field (Kholtoson vein deposit) and the stockwork in the central part (Inkur stockwork deposit). The ore mineral composition is similar at both deposits. Quartz is the main gangue mineral; there are also present muscovite, K-feldspar, and carbonates. The main ore mineral of both deposits is hubnerite. In addition to hubnerite, at both deposits, more than 20 mineral species were identified; they include sulfides (pyrite, chalcopyrite, galena, sphalerite, bornite, etc.), sulfosalts (tetrahedrite, aikinite, stannite, etc.), oxides (scheelite, cassiterite), and tellurides (hessite). The results of mineralogical and fluid inclusions studies allowed us to conclude that the Inkur W and the Kholtoson W deposits were formed by the same hydrothermal fluids, related to the same ore-forming system. For both deposits, the fluid inclusion homogenization temperatures varied within the range ~195–344 °C. The presence of cogenetic liquid- and vapor-dominated inclusions in the quartz from the ores of the Kholtoson deposit allowed us to estimate the true temperature range of mineral formation as 413–350 °C. Ore deposition occurred under similar physical-chemical conditions, differing only in pressures of mineral formation. The main factors of hubnerite deposition from hydrothermal fluids were decreases in temperature.
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Yanishevskya, Elena, Nadezhda Fokina, Ekaterina Selivanova, Alena Kompanchenko, Dmitriy Makarov e Andrey Goryachev. "Processing of Sulfide Copper-Nickel Ores from the Deposits in Murmansk Region by Heap Leaching". Minerals 11, n.º 8 (28 de julho de 2021): 820. http://dx.doi.org/10.3390/min11080820.
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The feasibility of processing low-grade copper-nickel ores by heap bioleaching was investigated. It was found that an iron-oxidizing strain of acidophilic microorganisms, Acidithiobacillus ferrivorans, is effective in the leaching of sulfide ores from the deposits in Russia’s Murmansk region. Sulfide mineralization of the studied mineral feeds was described using the methods of X-ray phase analysis and optical microscopy. In the process of leaching, the pH and Eh values and the concentrations of ferric and ferrous iron, nickel, and copper ions were monitored. By the end of the experiment, 16.5% of nickel and 7.5% of copper was recovered from the ore of the Allarechensk technogenic deposit, while 22.5% of nickel and 12.7% copper were recovered from the ore of the Nud II deposit. By silicate analysis of the solid phase, patterns of ore chemistry change were described during the process of bioleaching.
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ONO, Shuji, e Juichi SATO. "Gold and silver ores from the Ezuri Kuroko ore deposits, Akita Predecture, Japan." JOURNAL OF MINERALOGY, PETROLOGY AND ECONOMIC GEOLOGY 90, n.º 8 (1995): 268–79. http://dx.doi.org/10.2465/ganko.90.268.
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Varentsov, I. M., e V. N. Kuleshov. "Rare elements — setting markers of the formation of the manganese and iron ore deposits of Kalahari and Postmasburg areas (South Africa). Communication 2. Iron- and manganese ore of Postmasburg area". Литология и полезные ископаемые, n.º 5 (20 de outubro de 2019): 466–85. http://dx.doi.org/10.31857/s0024-497x20195466-485.
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In the world resources of manganese and iron ores, a significant place belongs to the Postmasburg ore field (South Africa), enclosed in rocks of the Transvaal Supegroup. Ore deposits have the nature of karst residual accumulations. A number of elements (B, Cr, Ni, Zn, Ge, As, Se, Mo, Ag, Cd, Sb, Te, W, Pb, REE) form a characteristic association that sheds light on the geochemistry of the ore formation processes. Of these, the most representative elements are: Mo, As, Ag and REE. Molybdenum is distinguished by the chemisorption incorporation nature of accumulation in the ores under consideration, often with the formation of epic growths of ferri molybdate-type minerals. Arsenic leached from substrate rocks and accumulated in karstic Mn-Fe- and Fe-ores reflects the total effect of the dominant iron oxide minerals on its mobility. The behavior of silver is controlled by the processes of hypergenic change of Archean-Early Proterozoic carbonate rocks and banded iron ores (BIF). Comparison of the distribution of REE in karst Fe-, Mn-Fe- and Mn-ores and in banded iron ores shows that they are characterized by similar values of cerium (C/Ce*) and europium (Eu/Eu*) anomalies, but differ in the fractionation of heavy and light REE (typical values: Ce/Ce* = 0.7‒1.0; Eu/Eu* = 0.8‒1.1). Strip iron ores and associated manganese ore deposits accumulated in the marginal anoxide-disoxide marine basin, which was limited to continental land. Anoxide and disoxide conditions were the result of intense hydrothermal activity.
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Galyamov, A. L., A. V. Volkov, K. Yu Murashov, N. V. Sidorova e T. P. Kuznetsova. "Prospects for identifying the Mississippi Valley type deposits in the North-East of Russia". LITHOSPHERE (Russia) 20, n.º 2 (25 de abril de 2020): 254–70. http://dx.doi.org/10.24930/1681-9004-2020-20-2-254-270.
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Research subject. The Mississippi Valley type deposits make up about a third of the global balance of lead and zinc reserves, resources and production. Additionally, silver, antimony, arsenic, barium, bismuth, cadmium, cobalt, gallium, indium, mercury, molybdenum, nickel and thallium can be present in the ores of these deposits. In the North-East of Russia, the Mississippi Valley type of deposits is poorly represented. In this work, we investigate the deposits of the Sardana ore cluster of the Republic of Sakha (Yakutia) and individual deposits of the Magadan region. Materials and methods. The article discusses the results of previous scientific research and new data on the geochemical features, isotopic composition of ores and geological and structural conditions for the formation of the Sardana cluster deposit. In addition, the potential for identifying stratiform lead-zinc deposits is associated with favourable geodynamic conditions in the region, as well as with the refinement and adaptation of the forecast-search model of MVT deposits for the North-East of Russia. Results. The mineralogical and geochemical features of the rocks and ores of the Sardana cluster deposits, the morphology of ore bodies, their zoning elements, as well as isotopic ratios indicate that the ores are likely to be of the Mississippi Valley type with the onset of ore deposition at early diagenetic and catagenetic stages. The distribution of rare elements indicates a significant role of superimposed metamorphism of the host carbonate-terrigenous strata in the deposition of the ores of producing stages. Conclusion. The potential possibility of increasing the mineral and raw material base of lead and zinc is associated with the identification of sedimentary basins with a stagnant anoxic regime of carbonate accumulation in the immediate vicinity of the development areas of rift complexes, as well as with the presence of other critically important forecast-search signs. In addition to the well-known Killakh metallogenic zone, Tuora-Sis and Orulgan metallogenic taxa located in the north of the Republic of Sakha (Yakutia) with known stratiform manifestations of lead and zinc belong to such areas.
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FEDOTOV, Pavel, Arkadiy SENCHENKO, Konstantin FEDOTOV e Aleksander BURDONOV. "Studies of enrichment of sulfide and oxidized ores of gold deposits of the Aldan shield". Journal of Mining Institute 242 (25 de maio de 2020): 218. http://dx.doi.org/10.31897/pmi.2020.2.218.
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The paper presents the analysis of studies of the enrichment of sulfide and oxidized ores in Yakutia deposits. The ore of the deposit is a mixture of primary, mixed and oxidized ores. The main useful component of the studied ore samples is gold with a content of 1.5 to 2.8 g/t, the silver content is low – 5-17 g/t. Ore minerals are represented by sulfides, among which pyrite predominates. The total sulfide content does not exceed 3-5 %. The presence in the ore of free and associated gold with a grain size from fractions of a micron to 1.5 mm. Gold is represented by nuggets in intergrowth with sulfides and also forms independent inclusions. Ores are classified as easily cyanidable.
It was found that the content of amalgamable gold is 10-49, the share of cyanidable gold ranges from 66.67-91, the share of refractory gold is 9.0-33.33 %, which in absolute amount equals to 0.24-0.8 g/t. The extraction of gold in gravitation concentrate varies depending on the gold content in the ore and the yield of concentrate and for ores with a gold content of 1.5-2.8 g/t from 40 to 60 %. The direct cyanidation of all studied ore samples established the possibility of extracting gold into solution up to 86.7-92.9 %, the gold content in cyanidation cakes is 0.2-0.3 g/t. Investigations of the gravitation concentrate by the method of intensive cyanidation showed that with an initial gold content of ~ 500 g/t, up to 98.9 % is extracted into the solution. The gold content in intensive cyanide cakes will be 6-15 g/t. A set of studies carried out by the authors of the article at various institutes showed that it is advisable to process ore from the deposit using cyanidation technology with preliminary gravitational extraction of gold.
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Boni, Maria, e Johan Yans. "Editorial for Special Issue “Supergene Evolution of Polymetallic Deposits, Including Non-Laterite Fe and Mn Ores”". Minerals 11, n.º 9 (30 de agosto de 2021): 946. http://dx.doi.org/10.3390/min11090946.
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Masloboev, Vladimir, Sergey Seleznev, Anton Svetlov e Dmitriy Makarov. "Hydrometallurgical Processing of Low-Grade Sulfide Ore and Mine Waste in the Arctic Regions: Perspectives and Challenges". Minerals 8, n.º 10 (7 de outubro de 2018): 436. http://dx.doi.org/10.3390/min8100436.
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The authors describe the opportunities of low-grade sulfide ores and mine waste processing with heap and bacterial leaching methods. By the example of gold and silver ores, we analyzed specific issues and processing technologies for heap leaching intensification in severe climatic conditions. The paper presents perspectives for heap leaching of sulfide and mixed ores from the Udokan (Russia) and Talvivaara (Finland) deposits, as well as technogenic waste dumps, namely, the Allarechensky Deposit Dumps (Russia). The paper also shows the laboratory results of non-ferrous metals leaching from low-grade copper-nickel ores of the Monchepluton area, and from tailings of JSC Kola Mining and Metallurgical Company.
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Rubtsov, Yu, А. Trubachev, E. Voronov, A. Lavrov e A. Lavrik. "INTENSIFICATION OF DISPERSED AND FINE-GRAINED SILVER EXTRACTION IN CYANIDE HEAP LEACHING OF GOLD". Transbaikal State University Journal 26, n.º 8 (2020): 40–48. http://dx.doi.org/10.21209/2227-9245-2020-26-8-40-48.
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Since the cost of gold has increased by an order of magnitude over the past 20 years, gold mining began to be carried out from ores that are not previously acceptable for heap leaching (HL) technology – these are refractory ores with thin and ultrafine inclusions of precious metals, ore with an increased silver content. In the Russian Federation, classical representations in the field of gold and silver HL prevail in design solutions. At the same time, the problem of silver leaching is considered in terms of the associated extraction of the main component. This approach is determined by a limited set of technological measures that have become an integral part of the classic technological regulation: ore crushing to the class –200–40 mm, sodium cyanide consumption at the level of 0,5 kg/t; pH value – 10,5; cycle duration 65 days or more; gold concentration in production solutions – fractions, mg/l; using activated carbon for sorption of noble metals. Processing ores with silver contents of 30 g/t and a more classical approach to gold HL does not allow to increase the degree of extraction. There is a need to modernize the circuit or change the parameters of the technological regulations. The object of the study was a sample of poor quartz ore provided by the customer developing one of the gold and silver deposits of the Far Eastern Federal District, the object was to increase the degree of leaching of silver from poor gold-bearing ores without changing the technological scheme and without attracting additional mining equipment. Critical analysis of literary data was carried out and the main directions of gold production from poor gold-bearing ores were identified. Chemical and mineralogical compositions of silver-containing minerals and ore rocks were investigated. Forms of association of silver with ore minerals and rocks have been established. The option of physical and chemical activation of increase of reactivity of cyanide solutions during heap leaching of silver from poor gold-bearing ores is chosen. In laboratory conditions, it was found that an increase in the concentration of sodium cyanide by 6 times or more contributes to a satisfactory extraction of gold both in agitation and percolation leaching of silver. However, in the latter case, the positive result was obtained only with the use of solutions with increased reactivity
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Kakavoyannis, Evangelos. "The silver ore-processing workshops of the Lavrion region". Annual of the British School at Athens 96 (novembro de 2001): 365–80. http://dx.doi.org/10.1017/s0068245400005335.
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The development in the Classical period of washeries where the crude ores were processed for smelting marked a big step forward in Athenian silver production, since they made it possible to exploit the hitherto unusable poorest argentiferous deposits. The discovery and excavation of the washeries and ergasteria have illuminated the technological advance from the pre-Classical two-phase to the Classical three-phase system. The earliest washeries were located perforce close to natural water sources, but when these became inadequate for the growing needs of the industry, ergasteria were built which, in addition to a washery, had a cistern to collect recyclable rainwater, and could thus be located close to the ore sources. Small communities in which the personnel lived and died grew up around them.
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Tanaka, Yoshiyuki, Hajime Miki, Gde Suyantara, Yuji Aoki e Tsuyoshi Hirajima. "Mineralogical Prediction on the Flotation Behavior of Copper and Molybdenum Minerals from Blended Cu–Mo Ores in Seawater". Minerals 11, n.º 8 (11 de agosto de 2021): 869. http://dx.doi.org/10.3390/min11080869.
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The copper ore in Chilean copper porphyry deposits is often associated with molybdenum minerals. This copper–molybdenum (Cu–Mo) sulfide ore is generally mined from various locations in the mining site; thus, the mineral composition, oxidation degree, mineral particle size, and grade vary. Therefore, in the mining operation, it is common to blend the ores mined from various spots and then process them using flotation. In this study, the floatability of five types of Cu–Mo ores and the blending of these ores in seawater was investigated. The oxidation degree of these Cu–Mo ores was evaluated, and the correlation between flotation recovery and oxidation degree is presented. Furthermore, the flotation kinetics of each Cu–Mo ore were calculated based on a mineralogical analysis using mineral liberation analysis (MLA). A mineralogical prediction model was proposed to estimate the flotation behavior of blended Cu–Mo ore as a function of the flotation behavior of each Cu–Mo ore. The flotation results show that the recovery of copper and molybdenum decreased with the increasing copper oxidization degree. In addition, the recovery of blended ore can be predicted via the flotation rate equation, using the maximum recovery (Rmax) and flotation rate coefficient (k) determined from the flotation rate analysis of each ore before blending. It was found that Rmax and k of the respective minerals slightly decreased with increasing the degree of copper oxidation. Moreover, Rmax varied greatly depending on the mineral species. The total copper and molybdenum recovery were strongly affected by the degree of copper oxidation as the mineral fraction in the ore varied greatly depending upon the degree of oxidation.
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Tămaș, Călin Gabriel, Mădălina Paula Andrii, Réka Kovács, Sergiu Drăgușanu e Béatrice Cauuet. "Sphalerite Composition in Low- and Intermediate-Sulfidation Epithermal Ore Bodies from the Roșia Montană Au-Ag Ore Deposit, Apuseni Mountains, Romania". Minerals 11, n.º 6 (15 de junho de 2021): 634. http://dx.doi.org/10.3390/min11060634.
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We evaluated the significance of the iron and manganese content in sphalerite as a tool for distinguishing between low-sulfidation and intermediate-sulfidation epithermal deposits on the basis of new and previously published electron probe microanalyses data on the Roșia Montană epithermal ore deposit and available microchemical data from the Neogene epithermal ore deposits located in the Apuseni Mountains and Baia Mare region, Romania. Two compositional trends of the Fe vs. Mn content in sphalerite were delineated, a Fe-dominant and a Mn-dominant, which are poor in Mn and Fe, respectively. The overlapping compositional range of Fe and Mn in sphalerite in low-sulfidation and intermediate-sulfidation ores suggests that these microchemical parameters are not a reliable tool for distinguishing these epithermal mineralization styles.
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Novakov, Roman, Valentina Kungurova e Svetlana Moskaleva. "Formation conditions of noble metal mineralization in sulfide cobalt-copper-nickel ores of Kamchatka (on the example of Annabergitovaya Schel ore occurrence)". Journal of Mining Institute 248 (25 de maio de 2021): 209–22. http://dx.doi.org/10.31897/pmi.2021.2.5.
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The authors present research results, the purpose of which is to study the specifics of noble metal mineralization and its genesis in sulfide cobalt-copper-nickel ores of the Kamchatka nickel-bearing province. The paper is dedicated to one of its many ore occurrences called Annabergitovaya Schel (Annabergite Gap). The material composition of platinoid, silver, gold, bismuth and tellurium minerals, as well as sulfarsenides in the ores of this occurrence was investigated. Based on the data of mineral formation sequence and the use of geosensors, conclusions were drawn regarding the genesis of noble metal mineralization.
Formation of platinoid minerals, silver and gold at the Annabergitovaya Schel ore occurrence is mainly associated with the epigenetic effect of post-ore granitoids on ore-bearing intrusion rocks of the Dukuk complex of the cortlandite-norite formation and on syngenetic ores. An early association of noble metal minerals is represented by sperrylite, irarsite, and rare unnamed phases of Pt + Ir + Te. Irarsite and Pt + Ir + Te phases were formed at the contact-metasomatic stage. Sperrylite can be assumed to be of magmatic origin. Silver sulfides and tellurides, silver and palladium bismuth tellurides, and native gold were formed at the late, hydrothermal-metasomatic, stage. The occurrence conditions of mineral parageneses, associated with noble metal mineralization, correspond to the formation of shallow-depth metasomatic rocks (5 km). Sub-developed quartz-feldspar metasomatites, associated with the formation of early platinoid arsenides and sulfarsenides, are in equilibrium with circumneutral solutions (pH of 4.5-6.5) at temperatures of 350-600 °C. Late hydrothermal association with Pd, Ag and Au minerals is close to propylites and was formed at pH values of 4.5-6.5 and temperature of 150-350 °C.
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THALHEIM, KLAUS. "THE 1477 SILVER FIND AT THE ST. GEORG MINE IN SCHNEEBERG AND SIGNIFICANT ORE SPECIMENS IN THE MUSEUM OF MINERALOGY AND GEOLOGY IN DRESDEN". Earth Sciences History 38, n.º 2 (1 de novembro de 2019): 157–72. http://dx.doi.org/10.17704/1944-6178-38.2.157.
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ABSTRACT Two silver ore specimens in the mineralogical collection of the Senckenberg Natural History Collections Dresden, Museum of Mineralogy and Geology, are samples from one of the most spectacular silver finds in Saxon Erzgebirge. The history of the find and of the two silver ore specimens is discussed. The origin of such a rich deposit of silver ore is examined in relationship to the geology of mineral deposits.
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Chiarantini, Laura, Marco Benvenuti, Giovanna Bianchi, Luisa Dallai, Vanessa Volpi e Rosarosa Manca. "Medieval Pb (Cu-Ag) Smelting in the Colline Metallifere District (Tuscany, Italy): Slag Heterogeneity as a Tracer of Ore Provenance and Technological Process". Minerals 11, n.º 2 (20 de janeiro de 2021): 97. http://dx.doi.org/10.3390/min11020097.
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Archaeological investigations of the Colline Metallifere district (Southern Tuscany, Italy) have highlighted several Medieval sites located close to the main Cu-Pb-Fe (Ag) ore occurrences. This study is focused on the investigation of late-medieval slags from Cugnano and Montieri sites using both geochemical and mineralogical methods to understand slag heterogeneities as result of ore differences and technological processes. Matte-rich slags present in both sites (with abundant matte ± speiss and frequent relict phases) represent waste products related to primary sulphide ore smelting to obtain a raw lead bullion. The distribution of slags between the Ca-rich or Fe-rich dominant composition, and the consequent mineralogy, are tracers of the different ore–gangue association that occurred in the two sites. Silver is present only in very small matte-rich slags and ores enclosed within the mortar of the Montieri site; wastes derived from silver-rich mineral charges were probably crushed for the recovery of silver. Matte-poor slags found at Montieri represent a second smelting; raw lead bullion obtained from matte slags (both Fe- and Ca-rich) was probably re-smelted, adding silica and Al2O3-phase-rich fluxes, under more oxidizing conditions to reduce metal impurities. This second step was probably employed for Zn-rich lead ores; this process helped to segregate zinc within slags and improve the quality of the metal.
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El-Hasa, Tayel. "SYNCHROTRON BASED MICRO-MAPPING AND XAFS INVESTIGATION OF Fe-Mn AND EPIGENETIC INTERGROWTH WITHIN THE CAMBRIAN SHALLOW MANGANESE DEPOSITS, SOUTH JORDAN". Iraqi Geological Journal 53, n.º 1A (31 de janeiro de 2020): 117–27. http://dx.doi.org/10.46717//igj.53.1a.r7.2020.01.28.
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The current work investigates the Cambrian Manganese ore deposits from Wadi Dana at central Wadi Araba region. This investigation aims to unravel the chemistry and micro-textures of the mineral paragenetic sequence for these manganese ore deposits. Particularly the Fe–Mn intimate intergrowth micro texture and the epigenetic Mn mineralization associated with Cu minerals. The combination of the synchrotron-based X-ray fluorescence (syn-XRF) micro-mapping and X-ray absorption fine structure (XAFS) techniques were used. They provide a clear picture of the elemental distribution of Mn, Fe, Cu, and Pb and other elements presented within the ore micro textures. Besides, it determines the exact elemental speciation. The results obtained gave a better understanding of the elemental atomic structures and eventually the depositional environment. Particularly, the syn-XRF micro-mapping reveals the existing of many successive evolution stages in the Mn ores. Besides, the X-ray Absorption Near Edge Structure (XANES) results showed that the micro-rhythmic texture is changing from Mn+4 (Pyrolusite) into Fe+3 (Hematite). This is evidence for the role of Eh as the main controlling factor during the ore formation. Eventually, indicating tentatively the paleoceanography setting of the Mn deposits. This is related to the continuous transgression-regression on the sea level in a semi-closed sea.
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Nekrasov, E. M. "EXPECTED OCCURRENCE OF THE BLIND ORE BODIES AT THE LOWER LEVELS OF THE BALEI DEPOSIT AND A MECHANISM OF THE RICH ORES FORMATION AT THE NEAR-SURFACE GOLD-SILVER ORE DEPOSITS". Proceedings of higher educational establishments. Geology and Exploration, n.º 5 (28 de outubro de 2017): 40–51. http://dx.doi.org/10.32454/0016-7762-2017-5-40-51.
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The gold ore chimneys of 2 types have been shown to be developed at the near-surface deposits of gold and silver ores. These types are: 1 - bulk ones, of the vein-nested-veinlet ore bodies of stockwork shapes and 2 - small pay streaks of the ore bodies, appeared either in single veins or in the veins, being a part of the wide ore bundles. The example of the first type is the Central ore column of Balei deposit and the column of the Glavnaya (Main) vein of the Karamkenskoe deposit. A deiailed analyses of the graphic material, made by N.V. Petranovskaya for Balei deposit, confirms, that under the bottom of the ore controling vein №2 in the vertical interval from 100 to 250-350 m the rich ores can be prevailed in the zones, which are likely to join with ore bodies of Taseevsky site. The discovery of the new bulk gold ore chimnies is likely to be there. With this, an additional exploration of the south-east flanks of the Balei deposit is needed, that can lead to the discovery of the new bulk gold ore chimnies.
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Berdnikov, N. V., V. G. Nevstruev, P. K. Kepezhinskas, V. O. Krutikova, N. S. Konovalova e I. A. Astapov. "SILICATE, IRON OXIDE AND COPPER-GOLD-SILVER MICROSPHERULES IN ORES AND PYROCLASTICS OF THE KOSTENGINSKOYE IRON ORE DEPOSIT (RUSSIAN FAR EAST)". Tikhookeanskaya Geologiya 40, n.º 3 (2021): 67–84. http://dx.doi.org/10.30911/0207-4028-2021-40-3-67-84.
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Iron-oxide ores and pyroclastics from the Kostenginskoye deposit in the Malyi Khingan (Russian Far East) contain numerous silicate, iron-oxide, and copper-gold-silver microspherules. Silicate spherules are composed of immiscible iron- and silica-rich glasses, gas cavities and mineral inclusions. Iron-oxide spherules include magnetite with minor ilmenite and Fe-rich silicate glass. Copper-gold-silver spherules contain inclusions predominantly of copper oxide compositions. The studied microspherules are considered to have formed during the rapid ascent of metal-silicate melts from depth and their degassing controlled by liquid immiscibility differentiation. The paper discusses the possible volcanic origin of iron-oxide ores and the associated noble metal mineralization for the deposits of this type.
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Lyons, James I. "Geology and ore deposits of the Bolanos silver district, Jalisco, Mexico". Economic Geology 83, n.º 8 (1 de dezembro de 1988): 1560–82. http://dx.doi.org/10.2113/gsecongeo.83.8.1560.
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Zhang, Huan, Jun Li, Tong Wei Luo e Wen Li Lv. "Geological Characteristics of the Changdong-Manxu Pb-Zn Deposit in Ninger, Yunnan and its Ore-Search Prospects". Advanced Materials Research 634-638 (janeiro de 2013): 3390–93. http://dx.doi.org/10.4028/www.scientific.net/amr.634-638.3390.
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Since the 1950s, the Changdong-Manxu Pb-Zn deposit has ever been explored for ore bodies by a number of Geology Parties，On the basis of studying the regional metallogenic geological background, Geologic characteristics of the deposits, ore-controlling geological factors, they thought the deposit belongs to sedimentary transformation type stratabound lead-zinc ore deposit ,which controlled by fault structures. According to the features of ore-controlling fault features and metallogenic conditions，it is possible to find large to super-large ores inside and outside the tectonic zones of the deposit.
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Kuleshevich, L. V. "Noble-metal associations related to Paleoproterozoic basic-hyperbasic magmatism in the Lapland-Onega province of Karelia". Vestnik of Geosciences 9 (2020): 14–18. http://dx.doi.org/10.19110/geov.2020.9.3.
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Topomineralogical studies are part of mineralogenic research conducted in the Paleoproterozoic Lapland-Onega rift-related structure in Karelia. These studies are important because of the location of promising areas and the study of deposits associated with basic-hyperbasic magmatism in Paleoproterozoic rift-related structures (chromite, titanomagnetite and nickel ores with PGE and gold). The aim of mineralogenic studies is to better understand major ore and noble-metal mineral associations by microprobe and ICP-MS-analyses. It was found that chromite ores are accompanied by high-temperature associations of platinoids — arsenides, sulfo-arsenides Pt, Rh, Ir and bismutotellurides Pt (with Pd), and sulfide Cu-Ni ores — mainly Pt-Pd bismutotellurides and tellurides. Titanomagnetite ores with low-sulfide copper mineralization contain stibio-sulfoarsenides, antimonides, stannides, and more rarely sulfides of Pd, Pd-Pt, and silver-containing gold.
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MELNIKOV, ANTON VLADIMIROVICH, PAVEL IVANOVICH ROMANOV e TATIANA VLADISLAVOVNA ROMANOVA. "NEW DATA ON GEOLOGY AND GOLDENCE OF THE PROSPECTIVE AREAS «TAEZHKA» AND «UTRENNAYA» IN THE DAMBUKINSKY ORE DISTRICT (UPPER AMUR PRIAMURYE)". Messenger AmSU, n.º 91 (2020): 72–80. http://dx.doi.org/10.22250/jasu.12.
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Information is given on the gold bearing of the ore-prospective areas «Tayezhka» and «Utrenniya» of the Dambukinsky Оre District of the Upper Priamurye/ Taking into account new data on geology, geochemistry, real composition of ores, description and comparative analysis of gold-ore manifestations are given. The prerequisites for the formation and criteria for the forecast and search of industrial gold deposits in this area of Upper Priamurya are described: geotectonic and structural position, deep structure, formation features, hydrothermal changes of rocks, mineral and geochemical associations, tipomorphism of gold and ore minerals, etc.
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Yuningsih, ST., MT., Ph.D, Euis Tintin. "ORE MINERALS FROM KUROKO TYPE DEPOSIT OF TOYA-TAKARADA MINE, HOKKAIDO, JAPAN". Buletin Sumber Daya Geologi 11, n.º 2 (30 de agosto de 2016): 103–15. http://dx.doi.org/10.47599/bsdg.v11i2.14.
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Toya-Takarada mine is Au- and Ag-rich Kuroko-type deposit located in Takarada, Toya-mura, southwest Hokkaido, Japan. The deposits were hosted in rhyolitic tuff and mudstone of Middle Miocene age. Ore samples of fine-grained black ore, vuggy black-yellow ore, granular vuggy black ore, quartz-sulfide ore and massive quartz-barite ore were studied to identify the ore minerals association in the Toya-Takarada mine. The ore minerals are dominated by sphalerite, galena, chalcopyrite and pyrite with fewer amounts of electrum, tetrahedrite-tennantite, and other sulfosalt minerals with secondary mineral of covellite.The quantitative chemical analysis of ore minerals by EPMA indicated that FeS contents in sphalerite is low (0.3-1.2 mol.%) in all kinds of ore samples. Small grains of electrum as inclusions in pyrite are identified in vuggy black-yellow ore with Ag content around 32-33 atm %.In general, the silver minerals in Kuroko-type deposits occurred mainly in the black and yellow ores zone dominantly composed of sphalerite, galena, pyrite, chalcopyrite and barite as a form of electrum and/or argentian tetrahedrite-tennantite series. Thus, the massive quartz-barite ore sample of Toya-Takarada mine are also contain some rare silver sulfosalt minerals such as proustite, Cu-rich pearceite, geocronite-jordanite and fizelyite. Those minerals were found together in association with sphalerite. It seems that sphalerite was crystallized first followed by proustite and Cu-rich pearceite, then geocronite-jordanite and fizelyite are crystallized later.Sphalerites from quartz-sulfide ore of Toya-Takarada contain some fluid inclusions and measured homogenization temperatures are in the range of 164-247°C (av. 208°C) with salinity ranging from 1.9 to 4.7 wt.% NaClequiv. (av. 3.9 wt.% NaClequiv.). The mineral assemblage, iron content in sphalerite and silver content in electrum were indicated that sulfur fugacity was slightly higher during ore mineralization in Toya-Takarada mine.
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Simmons, Stuart F., e Kevin L. Brown. "Precious Metals in Modern Hydrothermal Solutions and Implications for the Formation of Epithermal Ore Deposits". SEG Discovery, n.º 72 (1 de janeiro de 2008): 1–12. http://dx.doi.org/10.5382/segnews.2008-72.fea.
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ABSTRACT We determined the concentrations of gold, silver, arsenic, antimony, and mercury in deep hydrothermal solutions (~1 km depth, 200° to >300°C) from active geothermal systems in the Taupo Volcanic Zone, New Zealand, and Ladolam, Lihir Island, Papua New Guinea. The wide range of concentrations in the New Zealand systems and the stable isotope signatures at Ladolam confırm that magmas are an important source of high concentrations of gold and silver in hydrothermal solutions. The Rotokawa geothermal system in New Zealand has the highest hydrothermal fluxes of gold (~30–100 kg/yr) and silver (~5000–11,000 kg/yr), which, if they remained constant, could match the metal inventories of the largest ore deposits in the world in <50,000 years. This relatively short time span is comparable to the amount of time required to account for the known gold resource in ores at Ladolam, which has a slightly lower gold flux (~25 kg/yr). The fact that a giant gold deposit exists at Ladolam, rather than at Rotokawa, demonstrates the importance of fluid focusing and effıcient metal deposition in the formation of epithermal gold and silver ore deposits.
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Kigai, I. N. "Formation Environments of Metasomatites and Ores of the Epithermal Gold–silver Deposits". Geology of Ore Deposits 62, n.º 5 (setembro de 2020): 432–37. http://dx.doi.org/10.1134/s1075701520050037.
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Li, Niannian, Yi Cao, Zhaonian Zhang, Yilun Du e Chenfang Guo. "Oxygen-Isotope-Based Modeling of the Hydrothermal Fluid Processes of the Taochong Skarn Iron Deposit, Anhui Province, China". Minerals 11, n.º 4 (2 de abril de 2021): 375. http://dx.doi.org/10.3390/min11040375.
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The Taochong iron deposit is one of the important skarn deposits in the Middle–Lower Yangtze River metallogenic belt, Eastern China. There are two types of ores in the deposit: skarn- and quartz–calcite-type ores. The skarn-type ore, which is composed of hematite (Hm-1), garnet, pyroxene, actinolite, chlorite, quartz (Q-1), and calcite (Cal-1), is crosscut locally by a quartz–calcite-type ore vein. The quartz–calcite-type ore consists mainly of hematite (Hm-2), magnetite, quartz (Q-2 and 3), and calcite (Cal-2). The δ18Owater value (~2.67‰) of the fluids in equilibrium with Hm-1 is similar to the values of the mixtures of magmatic and meteoric fluids. However, the δ18O values of the fluids in equilibrium with Hm-2 are in the range of 7.64–8.54‰, similar to those of magmatic fluids. The δ18O values decrease systematically from the fluids in equilibrium with Hm-2 (7.64‰ to 8.54‰) to the fluids in equilibrium with magnetite, Q-3, and Cal-2 (−0.12‰ to 4.17‰) and the fluids in equilibrium with Cal-3 (−2.17‰ to 0.36‰). These features of oxygen isotopes indicate that two episodes of hydrothermal activity took place in the Taochong deposit, and both episodes began with a magmatic origin and then progressively evolved by mixing with meteoric water. The results of quantitative simulations suggest that the deposition of the skarn-type ores was most likely caused by the mixing of magmatic and meteoric fluids, whilst the deposition of the quartz–calcite-type ores was most likely caused by the boiling of magmatic fluids and the mixtures of magmatic brine and meteoric water.
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Kosenko, A. V. "Improvement of sub-level caving mining methods during high-grade iron ore mining". Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu, n.º 1 (2021): 19–25. http://dx.doi.org/10.33271/nvngu/2021-1/019.
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Purpose. To improve of the sub-level caving mining methods during mining of deposits of high-grade iron ores by applying a rational mode and intensifying the ore drawing. Methodology. It included an analysis of scientific literature, design documentation and the practice of mining of deposits of high-grade iron-ores in complex geomechanical conditions of deep horizons of mines, to establish the formation of fundamentally new foundations of scientific-and-design solutions for the rational extraction of minerals; numerical (application a special computer software package PFC 3D) and physical (based on the application of volumetric physical models and equivalent materials) modeling of ore drawing, aimed at identifying regularities of recovery process depending on the mining-geological and mining conditions of the mining of deposits, and also the physical- and-mechanical properties of the loosened ore mass. Findings. Regularities of changes in the qualitative and quantitative recovery percentages depending on the intensity of the ore drawing and physical-and-mechanical properties of the ore have been established using numerical and physical simulation. The obtained regularities made it possible to substantiate the rational parameters of the structural elements of the technological scheme for drawing and delivery of ore. A linear-alternating condition of ore drawing was developed, which will ensure an increase in the extraction of pure ore up to 10% and, as a result, up to 4.6% of quantitative and up to 5.2% of qualitative indicators of ore percentages, as well as up to 1.5% of absolute quality of mined ore mass. Originality. Power-law dependencies of the change in the angle of ore tapping on the intensity of the ore drawing and the ultimate strength of the ore for uniaxial compression have been established as well as dependencies of the increase in the volume of the tapping figure, when a linear-alternating condition of ore drawing is applied, on the intensity of the ore drawing, the height of the collapsed ore layer and the ultimate strength of the ore for uniaxial compression. Practical value. A linear-alternating condition of ore drawing has been developed, the implementation of which in practice makes it possible to increase the qualitative and quantitative recovery percentages and eliminate the human factor while observing the ore drawing planograms.
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Mammedov, Аlesger, Shahbeddin Musaev, Yaroslava Poshivaylo e Grigory Fedotov. "GI support of geological exploration of non-ferrous metal ore deposits". InterCarto. InterGIS 26, n.º 2 (2020): 120–36. http://dx.doi.org/10.35595/2414-9179-2020-2-26-120-136.
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Geoinformation technologies are applied, without exaggeration, in all spheres of human activity, and the geological industry is no exception. Geoinformation systems in geology help to solve a number of practical problems. Geologists specializing in mineral exploration use a variety of data sets to search for new, cost-effective deposits, from geological maps, hyperspectral aerial photographs and multispectral satellite imagery to databases of various formats. The geographic information system is an ideal platform for combining such heterogeneous information and its subsequent analysis. The article describes the experience of the national mining company of the Republic of Azerbaijan CJSC AzerGold in the use of geographic information systems in the exploration of non-ferrous metal deposits using the example of the development of the Filizchay and Aghyokhush deposits. The authors considered production problems, described the problems that arise at the stage of exploration and proposed methods for solving them, the need for the integrated use of information systems in exploration when searching for deposits of non-ferrous metals is noted. A database structure has been developed for the purpose of geological exploration of non-ferrous metal ores, including sections such as topography, geochemistry, geophysics, structural geology. The structure of geoinformation support for geological exploration of non-ferrous metal ores is proposed, which combines the functionality of geographic information systems (GIS) and mining geological information systems (MGIS). The stages of geoinformation processing of initial data are illustrated, on the basis of which a geological exploration strategy was formed at the Filizchay pyrite-polymetallic deposit, and then the optimal places and number of wells, coordinates, directions and angles of incidence of wells were determined quickly and with high accuracy, as well as the resource potential was specified. The role of interpolation methods in determining the primary exploration wells in the exploration of the Agyokhush gold deposit is disclosed.
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Vikentyev, Ilya, Olga Vikent’eva, Eugenia Tyukova, Maximilian Nikolsky, Julia Ivanova, Nina Sidorova, Dmitry Tonkacheev et al. "Noble Metal Speciations in Hydrothermal Sulphides". Minerals 11, n.º 5 (3 de maio de 2021): 488. http://dx.doi.org/10.3390/min11050488.
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A significant part of the primary gold reserves in the world is contained in sulphide ores, many types of which are refractory in gold processing. The deposits of refractory sulphide ores will be the main potential source of gold production in the future. The refractory gold and silver in sulphide ores can be associated with micro- and nano-sized inclusions of Au and Ag minerals as well as isomorphous, adsorbed and other species of noble metals (NM) not thoroughly investigated. For gold and gold-bearing deposits of the Urals, distribution and forms of NM were studied in base metal sulphides by laser ablation-inductively coupled plasma mass spectrometry and by neutron activation analysis. Composition of arsenopyrite and As-pyrite, proper Au and Ag minerals were identified using electron probe microanalysis. The ratio of various forms of invisible gold—which includes nanoparticles and chemically bound gold—in sulphides is discussed. Observations were also performed on about 120 synthetic crystals of NM-doped sphalerite and greenockite. In VMS ores with increasing metamorphism, CAu and CAg in the major sulphides (sphalerite, chalcopyrite, pyrite) generally decrease. A portion of invisible gold also decreases —from ~65–85% to ~35–60% of the total Au. As a result of recrystallisation of ores, the invisible gold is enlarged and passes into the visible state as native gold, Au-Ag tellurides and sulphides. In the gold deposits of the Urals, the portion of invisible gold is usually <30% of the bulk Au.
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Skripchenko, V. V. "Electrical resistivity of ores and rocks from the ural zone ore deposits under unidirectional pressure". Soviet Mining Science 24, n.º 2 (março de 1988): 105–9. http://dx.doi.org/10.1007/bf02497830.
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Savva, N. E., A. V. Volkov, A. A. Sidorov, E. E. Kolova e K. Yu Murashov. "Primorskoye epithermal Ag-Au deposit (Northeast of Russia): geologic aspects, mineralogic and geochemical features, and ore formation conditions". Геология рудных месторождений 61, n.º 1 (15 de janeiro de 2019): 52–74. http://dx.doi.org/10.31857/s0016-777061152-74.
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As a potentially large Ag-Au epithermal deposit, Primorskoye comprises the following three areas: Kholodny, Spiridonych, and Teply. This deposit is located in the Omsukchan district of the Magadan Region, where similar deposits, including Dukat, Lunnoye, Goltsovoye, Arylakh, Tidit, and Perevalnoye, have developed. The deposit can be attributed to the Kalalagian volcano-tectonic depression and is localized in a flat-lying rock mass in the Late Cretaceous ignimbrites and rhyolites having thicknesses of greater than 700 m, which is cut through by numerous dykes of medium and major composition. According to the drilling data, the solid mass of leucocratic granites is located in deposits at a depth of 400–500 m with outcrops in the northeastern part of the ore field. The presence of Bi-containing galena and matildite, the availability of mid and high temperature facies of metasomatites (epidote and actinolite), and the specific physical and chemical conditions during the formation of the epithermal Ag-Au ores indicate the intrusive position above and the role of granitoids as generators of high temperature magmatic fluids, which introduced Bi and heated the rocks enclosing the mineralization. The geochemical features of the ores are well correlated with their mineral compositions. The high concentrations of Mn and Ag, elevated concentration of Au, low concentrations of Cu, Pb, Zn, Sb, As, Bi, and Te, low sum of REE, and negative Eu- and positive Се-anomalies were observed. The high values of the Te/Se, Sr/Ba, Y/Ho, and U/Th indicators in the ores are associated with the deposit location in the zone of granitoid massif effect. Further, the physical and chemical parameters of ore formation in the Teply area are unusual and are characterized by high temperatures, low concentrations of salts, and fluid density, which are indicative of the typical “dry steam” conditions. The obtained results allow the Primorskoye epithermal deposit to be attributed to the intermediate class. The information present in the article is practically valuable for the regional forecast and metallogenic developments as well as for searching and assessing the epithermal Ag-Au deposits.
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Lavrik, Natalya, Natalya Litvinova, Tatyana Aleksandrova, Valentina Stepanova e Alexandra Lavrik. "Platinum mineralization comparative characteristics of the some Far East deposits". E3S Web of Conferences 56 (2018): 04017. http://dx.doi.org/10.1051/e3sconf/20185604017.
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In this article shown platinum mineralization comparative characteristics for three deposits: Kondoer-traditional unique deposit and other two probably alternative source of platinum: the Poperechnoe ironmanganese deposit and the Malmyzh copper-porphyry deposit. Platinoids of the Kondoer deposit are the chain Pt>>Ir>Os>Ru=Rh>Pd. The presences of platinum crystals are characteristic, there are over 50 rare and new platinoids minerals in different combinations. There are gold and silver. Platinoids from the iron-manganese ore of Poperechnoe are as Pt>>Rh≈Ir>Ru≈Os>Pd. A scattered dissemination of arsenide sulfate and sulfides of Rh, Ir, Ru, Os are noted in the platinum. Palladium is present as impurities in gold and platinum. The gold content is different-with admixtures Ag, Pb, Cd, Fe. At this stage the platinoids content in oxidized ores of the Malmyzh gold-copper porphyry deposit is Pt ≈ Pd. The gold is present as electrum. There is native silver cadmium.