Platinum-Group and Chalcophile Element Distributions in Ni-Cu-(PGE) Ores at Rozany Deposit, Bohemian Massif
Abstract
The Rozany deposit hosts massive and disseminated low-grade Ni-Cu-(PGE) ores associated with gabbroic dykes (400 Ma). The ores are characterized by predominant occurrence of pyrrhotite (up to 82 vol. %) accompanied by chalcopyrite, minor Fe-Ni sulfides (violarite and pentlandite) and rare pyrite and galena.
The mineralized rocks are strongly enriched in chalcophile (e.g., Se, Te, Bi) platinum-group elements (PGE) and rhenium with total PGE contents up to similar to 200 ppb. The pyrrhotite-dominated massive ores contain very high total I-PGE (Os, Ir, Ru) and Re contents paralleled (asi lepe accompanied) by low Pt and only elevated Pd concentrations.
In contrast, the Cu-rich ores exhibit high Pt-Pd contents contrasted at relative low I-PGE values. In addition to previously reported platinum-group minerals (PGM) such as sperrylite and unnamed Pd-tellurides, we newly identified Pt-Te-Bi-(Pd-Pb) (most likely moncheite) and Pt-As-Te (vincentite?) phases.