Home – Home – Jornals – Russian Geology and Geophysics 2020 number 3

Data on gabbro-dolerite pyrite-chalcopyrite-pyrrhotite, quartz vein sphalerite-chalcopyrite, and associated early and late gold-telluride-palladium mineralization of the Krutoi ore occurrence (Pai-Khoi Ridge, Yugor Peninsula) are presented. The early (magmatic) gold-telluride-palladium mineralization is represented by minerals of the ternary system Ag-Au-Cu, palladium antimonides and stibiotellurides, and platinum arsenides, and the late (hydrothermal) one, by minerals of the binary systems Au-Ag and Au-Pd as well as mercury, lead, and silver tellurides. Sudburyite and testibiopalladite have been first found in the Krutoi ore occurrence; moreover, testibiopalladite has been first discovered in the Pai-Khoi Ridge. Their chemical compositions and Raman spectra have been examined. The results of sulfide sulfur, oxygen, and carbon isotope studies of calcium-containing minerals of chalcopyrite-quartz veinlets suggest assimilation of the material of the host deposits by the ore-forming mantle fluids. The fluid inclusions in the veinlets are divided into nitrogen-methane and carbon dioxide-nitrogen according to the composition of the gas phase. It has been established that the mineral-forming fluids were poorly saturated with gas. Magnesium and calcium salts were predominant in them. The temperature of the formation of quartz in the chalcopyrite-quartz veinlets is close to 300-490 °C, and sphalerite-chalcopyrite and associated late gold-telluride-palladium mineralization formed at temperatures not exceeding 260 °C.