PGE and Au minerals from the low-sulfide ore of the Pana Tundra Pluton,Kola Peninsula

The PGE minerals (PGM) in the low-sulfide ore of the Pana Tundra intrusion have been studied in the Northern and Southern reefs, Eastern Chuarvy and Churozero sites. Forty mineral species and five mineral phases of PGE and Au have been identified. The early magmatic sulfide-telluride-sulfarsenide assemblage and the late redeposited arsenide-telluride assemplage are distinguished on the basis of relationships between minerals and morphology of PGM. Toward the upper part of the intrusion and from the west eastward, the contribution of Pt- and Pd-sulfides to ore regularly decreases along with an increase in the amounts of Pt- and Pd-arsenides depending on the sequence of crystallization of host rocks and degree of their postmagmatic alteration. Microprobe analyses and variation in chemical compositions of PGM pertaining to the braggite-vysotskite, eoncheite-merenskyite, and kotulskite-sobolevskite isomorphic series are given.