Hydrothermal quartz veins with Bi-bearing sulfidic mineralization and Bi-tellurides at the Gemerská Poloma talc deposit, Spišsko-gemerské rudohorie Mts., Slovakia

Epigenetic hydrothermal quartz veins with mineral associations of Bi-bearing sulfides and sulfosalts with Bi-tellurides penetrate the rock environment of the Gemerská Poloma talc-magnesite deposit in the Central Western Carpathians in Slovakia. The main exploited mineral is talc. The newly discovered occurence of quartz-sulfidic veins within the talc-magnesite deposit was studied in detail. The association of sulfosalts and sulfides is represented by the dominant minerals of the tetrahedrite group, bournonite, pyrite, cobaltite, and arsenopyrite together with less common to rare galena, minerals of the aikinite-bismutinite group (Naik 0.3 – 38.6—bismuthinite-pekoite-gladite), native bismuth, nuffieldite, cosalite and jonassonite. Later fluid contributions led to the formation of tellurides, which are represented by rare hedleyite and tetradymite associated with ikunolite. Mineral associations indicate that the deposit was invaded by multiple phases of mineralization. An open system between the granite and the talc carbonate body is indicated by the formation of zavaritskite, which occurred as a result of low-temperature F-rich fluids. Bismuth and fluorine are most probably from the underlying granite, but source of Au, Co, Ni and Te is not clear. Chemical and heat exchanges between the granite and the overlying carbonate body along the shear zone resulted in sulfide mineralization that was dominantly controlled by hydrothermal activity.