Mineralogical and Petrographic Features and Mineral Formation Sequence of Gold-Antimony Ores from Udereyskoe Deposit (Krasnoyarsk Region)

The article presents results of petrographic and mineralogical studies of gold-antimony ores of the Udereyskoe deposit and their concentration products. The main mineral associations of ores are characterized, mineral forms of occurrence are revealed, and distribution of Au, Pd, Ag is estimated. The paragenetic scheme of mineral formation sequence was clarified and supplemented. The important mineral forms of gold occurrence are goldbearing arsenopyrite and native gold (Au,Ag), as well as rare aurostibite AuSb2 and intermetallides such as antimony gold (Au,Sb), and palladium gold (Au,Pd). The revealed diversity of forms of noble metals and analysis of their relationships with associating sulfides and nonmetallic minerals indicate at least two contrasting early and late stages of ore genesis. Early quartz-pyrite and late pyrite, which are two stages of mineralization, are determened within the early stage. Three consecutive stages of mineralization are established in the late stage: quartz-stibnite, pyrite-stibnite-quartz, and pyrite-arsenopyrite-stibnite.