Preparability research on metasomatic ores and rocks of “Vostok-2” deposit

Abstract

The research for examination of elemental composition of typical metasomatic rocks and ores have been carried out According to the data of mineral and petrographic analysis of twenty transparent sections in parallel and crossed Nicols, specific associations of minerals in ore of current production at “Vostochnyi” mine have been determined. Flotation testing on beneficiation of tailings of core geological samples has been conducted. Substantial redistribution of valuable mineral from easy ores to diluting rocks has been noted. The percent of greisen ore, with coarse scheelite grains, has become extremely rare and on the average is 2 - 2.5% of gross mass of scheelite-quartz ore. The appearance of skarn minerals relicts and, at times, areas of skarn minerals in scheelite-sulphide ores leads to formation, in the near-vein spaces, of scheelite-biotite, scheeliteamphibole, scheelite-piroxene, scheelite-chlorite and scheelite-mica complex associations. Impregnations of scheelite have been found in quartzous rocks, the composition of mother rocks may be diverse (skarn, skarnified or biotite hornfels, quartzites). The number of dispersed single scheelite grains in rock and anhedral grains in near-vein spaces adjacent to veins with high scheelite concentration has grown. The content of СаСО3 which is conditioned by the presence of Ca-containing minerals in the composition of skarn in the shape of thin (fine) grain crystalline impregnation along the crevices and cleavage faces with formation of thin microveinlets, often together with quartz has increased. The calculation of expected extraction has evaluated the drop of scheelite extraction from feed of Primorskaia ore-processing plant in saleable concentrate of down to 3 %.