Diagenesis of clastic ores of the Ishkininо Co-bearing massive sulfide deposit (Southern Urals): Mineralogical-geochemical data and thermodynamic modeling

Research subject. The transformed clastic ores (ore diagenites) of the Ishkinino Co-bearing massive sulfide deposit hosted by serpentinites Main Uralian Fault Zone. Materials and methods. structures textures were stu died. trace element contents sulfides oxides determined using LA ICP MS. physical chemical modeling diagenetic formation accessory As minerals was conducted Selektor program package. Results. are gravelites with angular rounded clasts serpentinites, chromite in psammitic matrix same mineral composition. No hydrothermal remain gravelites; they replaced crystalline pyrite-2, porous pyrite-3, anhedral pyrite-4, pyrrhotite, chalcopyrite magnetite. Chalcopyrite magnetite replace all sulfides, sulfarsenides, gangue minerals. Chromite occurs as fragmented crystals or inclusions into serpentinite clasts. hosts euhedral cobaltite nickeline, gersdorffite native gold inclusions. Crystalline pyrite-2 is characterized higher Mn, Co, Ni, Cu Zn contents. Porous pyrite-3 exhibits Se Anhedral pyrite-4 enriched most comparison other pyrite generations. Se. Pyrrhotite contains highest Ni hi gher Co Conclusions. main elements (Co Ni), well Cu, not only but also oxides. Thus, while Mn Cu. Selenium similar quantities. Tellurium mostly concentrated pyrite-4. A comparative analysis our results those reported on deposits showed that serpentinite-sulfide had been intensely during diagenesis, which resulted low sulfides. alteration led to authigenic cobaltite, gersdorffite, nickeline a result release from primary Thermodynamic mode ling possibility As-bearing (in particular, nickeline) at temperatures 200°C below.