Gold-Sulfide Mineralization in the Manitanyrd Region, Polar Urals, Russia

This article describes the characteristics of gold-sulfide-quartz and gold-sulfide (gold-arsenic) ore occurrences in the Manitanyrd region of the Polar Urals. Ore occurrences are confined to NE-trending shear zones and have the common features of a geological structure. The host rocks are metamorphosed volcanic and volcanic-sedimentary rocks. We analyzed the mineral and chemical composition of the ore mineralization in all studied ore occurrences, showing that they belong to the same mineral type-pyrite-arsenopyrite, with a variable ratio of the main minerals. Arsenic pyrite is present in all ore occurrences. Two stages of ore formation were distinguished: early gold-pyrite-arsenopyrite with finely dispersed gold and late gold-galena-chalcopyrite-sphalerite with coarse gold, fahlore, and sulfosalts Pb, Cu, Bi, Sb. Native gold of the first generation, finely dispersed in arsenopyrite and pyrite, had an average to high fineness (800 & PTSTHOUSND;-1000 & PTSTHOUSND;) with a relatively low dispersion. Native gold of the second generation was larger, and its fineness in ore occurrences varied; in one of them, it varied from 300 & PTSTHOUSND; to 950 & PTSTHOUSND;, while in others, it varied from 800 & PTSTHOUSND; to 950 & PTSTHOUSND;. The isotope composition of sulfur in sulfides (& delta;S-34) ranged between -0.2 & PTSTHOUSND; and -8.0 & PTSTHOUSND;. & delta;S-34 values of sulfides in the range of -0.2 & PTSTHOUSND; to -3.5 & PTSTHOUSND; were similar to meteorite, indicating the participation of a single deep magmatic source of sulfur in the ore formation. According to the study of fluid inclusions, the formation of ore quartz veins occurs in the temperature range of 467-109 & DEG;C. The similarity of the geological-structural, mineralogical-geochemical, and isotope-geochemical features of the gold-sulfide-quartz and gold-sulfide occurrences in the area suggest their formation in a single hydrothermal system.