Mineralogical investigation of Ni- and Co-bearing sulfides from the Felsőcsatár talc schist, Hungary

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Abstract

Nickel and cobalt are critical raw materials essential for modern technologies and the energy transition. This study presents a detailed mineralogical investigation of the Ni–Co-bearing sulfides from the Felsőcsatár talc deposit, western Hungary. SEM–EDS and WDS analyses identified Ni-bearing pyrrhotite, Ni-rich pentlandite, violarite–siegenite and cobaltite–gersdorffite solid solution series, Ni-bearing pyrite, millerite, and ullmannite. The geological setting and mineralogical observations suggest that Ni and Co were originally derived from the ultramafic–mafic protolith, whereas hydrothermal and/or metamorphic processes are interpreted to have remobilized these elements and led to the formation of the Ni–Co-bearing mineralization. Subsequent supergene alteration resulted in the transformation of pentlandite into violarite.