MINERAL ASSOCIATIONS OF QUARTZ-SULFIDE ORES, ZUN-KHOLBA GOLD DEPOSIT, EASTERN SAYANY

DOI:10.24411/0869-5997-2020-10012

Abstract

The paper presents study results of mineral composition for the main quartz-sulfide ores within Zun-Kholba gold deposit, the largest in Eastern Sayany. Three mineral ore types are revealed: compact pyrite-pyrrhotite, quartzcarbonate-sulfide and quartz-polymetallic. Native gold is represented by four morphological types: rounded and drop-like inclusions in nonmetalliferous mass; irregular intergrowths with other ore minerals (galena, sphalerite, chalcopyrite); angular ingrowths of gold grains in quartz and pyrite; veinlet-like gold discharge along fractures in pyrite. However, no dependence of native gold composition on morphology as well as ore occurrence depth is noted. The general fineness values range varies from 350‰ to 950‰. In terms of mineral relationships, four ore associations are established: pyrite-pyrrhotite, quartz-carbonate-sulfide, quartz-polysulfide and sulfosalt corresponding to the preore stage and three successive ore formation stages.