SILVER IN THE ORE OF TUNGSTEN ANTONOV GORA DEPOSIT IN TRANSBAIKALIA
The relevance of the work lies in the need to justify the study of precious metals in ore bodies of tungsten deposits of the greisen formation, the aim of the work is a mineralogical and geochemical study of the silver content of tungsten ores, the object of study is the tungsten-sulfide-quartz veins of the Antonov Gora deposit, and the subject of its content and mineral forms of silver in them. Therefore, the research objectives were: a) to study the content of noble elements, primarily silver, in the tungsten-sulphide-quartz vein bodies of the Antonov Gora deposit, b) the mineral forms of silver in them and c) the relationships between silver and related chemical elements. The methodology consists in using quantitative mineralogical analysis of the heavy fraction of ground ore samples, optical and electron microscopy, and X-ray analysis to determine the mineral forms of silver. As a result of an integrated approach to the study of sulfide-wolframite ores of the Antonov Gora deposit of the greisen formation in Transbaikalia, high silver contents were determined in the range of 1...1068 ppm with an average grade of 45.4 ppm. If two samples with contents of more than 486 ppm are excluded from the calculation, it is 16.89 ppm. In ore containing bismuth in an amount of 0.075.0.243 % gold is also determined. Its content is in the range of 0.14.2.16 ppm. Silver is mainly found in wolframite-sulfide-quartz fragments of ore-bearing veins productive to tungsten. The predominant development of silver mineralization in mineral associations with a relatively high bismuth content has been established. They consist of pyrite, arsenopyrite, chalcopyrite, galena, sphalerite, bismuthinite, and cosalite. But a clear correlation between the content of bismuth and silver was not detected. To determine the mineral forms of silver, quantitative mineralogical analysis of the heavy fraction of ground ore samples and electron microscopy were used. It has been established that the carriers of silver are its own minerals, diaphorite, benjaminite and pyrargyrite, as well as cosalite, ksylingolite and bismite containing it as isomorphic impurities. Diaphorite was found in most samples of the heavy fraction in an amount of 0.001.0.008 %. Benjaminite, pyrargyrite, ksylingolite and bismite are represented by single individuals. The main carrier of silver is cosalite. Its content in the ore is in the range of 0.034.0.11 %. It contains 1.14.9.07 % silver. The study of these minerals will clarify the classification of silver-containing bismuth minerals and the position of silver in their structure. In this regard, it seems promising to study the possible silver content of the tungsten deposits Bukuka, Belukha, Dedov Gora, preserved in the 1960s. In this regard, ores and waste from their enrichment of the Spokoininsky, Bom-Gorkhonsky and Barun-Shiveinsky tungsten deposits should be investigated