Ore mineralogy of the Murtykty gold deposit is presented in the paper and main attention is paid to the mode of occurrence of precious metals. Ores are pyrite-bearing quartz-chlorite (±sericite, ±carbonate of the dolomite-ankerite series) metasomatites with variable ratios between rockforming minerals. Pyrite is the major sulfide; sphalerite, galena and chalcopyrite are secondary in abundance. Rare minerals include pyrrhotite, arsenopyrite, altaite, coloradoite, hessite, petzite, calaverite, volynskite, rucklidgeite, and native gold. The Ag content of native gold ranges from 6.11 to 35.32 wt. %. Significant amount of Au and Ag occurs in a telluride form: hessite Ag2Te, petzite Ag3AuTe2, calaverite AuTe2, and volynskite AgBiTe2. The refractory features of sulfide ores are caused by diverse modes of occurrences of precious metal.

Figures 8. Tables 6. References 15.

Key words: minerals of precious metals, gold, tellurides, Murtykty deposit, South Urals.

Yu.A. Paduchina, Institute of Mineralogy SU FRC MG UB RAS, Miass, Chelyabinsk oblast, 456317 Russia; padushina@mail.ru

N.S. Chukhareva, South Ural State University, Miass branch, ul. 8 Iyulya 10, Miass, Chelyabinsk oblast, 456316 Russia

K.A. Novoselov, Institute of Mineralogy SU FRC MG UB RAS, Miass, Chelyabinsk oblast, 456317 Russia;

E.E. Palenova, Institute of Mineralogy SU FRC MG UB RAS, Miass, Chelyabinsk oblast, 456317 Russia;

E.V. Belogub, Institute of Mineralogy SU FRC MG UB RAS, Miass, Chelyabinsk oblast, 456317 Russia;

I.A. Blinov, Institute of Mineralogy SU FRC MG UB RAS, Miass, Chelyabinsk oblast, 456317 Russia;

D.A. Artemyev, Institute of Mineralogy SU FRC MG UB RAS, Miass, Chelyabinsk oblast, 456317 Russia;

M.A. Rassomakhin, Institute of Mineralogy SU FRC MG UB RAS, Miass, Chelyabinsk oblast, 456317 Russia;

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