Chromites and accessory minerals in chromitites and ultramafic rocks of the Nurali massif (the South Urals)
Saveliev D. E., Zaikov V. V., Kotlyarov V. A., Zaikova E. V., Kraynev Yu. D.
Zapiski RMO (Proceedings of the Russian Mineralogical Society). 2017. V. 146. N 1. P. 59-84
New data on compositions of accessory and ore-forming chromites, as well as accessory sulfides and PGE minerals, are provided. From the west to the east, the compositions of chromites regularly vary from high-aluminous in spinel peridotites to high-chromium in dunites and chromitites and Fe- and Ti-rich ultramafic rocks of the wehrlite-clinopyroxenite complex. Nickel sulfides are typical accessory minerals of chromitites: millerite, pentlandite, heazlewoodite, and orcelite (?). Awaruite was found in the most of studied samples. The PGE minerals were studied from Mokraya Yama, Priozernoe and West Sherambai occurrences. They include laurite, erlichmanite, native osmium, iridium, ferroan platinum, Pd platinum, and minerals of the Pt—Pd—Cu, Pt—Fe—Ni, Pt—Cu, and Pt—Fe systems.
Key words: chromites, base metal sulfides, PGE minerals, ultramafic rocks, chromitites, Nurali massif, the South Urals.