PLATINUM MINERALIZATION OF THE SVETLOBORSKY AND KAMENUSHINSKY MASSIFS ( Urals Platinum Belt )
N.D. Tolstykha, Yu.M. Teleginb, and A.P. Kozlovc
aV.S. Sobolev Institute of Geology and Mineralogy, Siberian Branch of the Russian Academy of Sciences, pr. Akademika Koptyuga 3, Novosibirsk, 630090, Russia
bUrals-PGM (CJSC), ul. Vostochnaya 56, Office 817, Yekaterinburg, 620075, Russia
cResearch Institute of Comprehensive Exploitation of Mineral Resources, Russian Academy of Sciences, Kryukovskii tupik 4, Moscow, 111020, Russia
Keywords: Platinum mineralization, platinum group minerals, Ural-Alaskan type, Svetloborsky massif, Kamenushinsky massif
Pages: 603-619
Abstract
Platinum mineralization has been studied within two zoned clinopyroxenite-dunite massifs of the Urals Platinum Belt. Within the Svetloborsky massif, platinum group minerals (PGM) occur directly in serpentinized dunite. The ore-forming system demonstrates the features of an early evolutionary stage: a significant portion of PtFe alloys belongs to ferroan platinum; native osmium is depleted in Ir; an isoferroplatinum-osmium paragenesis is present. Within the Kamenushinsky massif, PGM are genetically related to chromitite and belong to the late-magmatic stage of the ore-forming system evolution: osmium and isoferroplatinum are rich in Ir; both isoferroplatinum-osmium and isoferroplatinum-iridium magmatic parageneses are present. The elevated Pt in the dunite of the Svetloborsky massif and in the chromitite of the Kamenushinsky massif is the result of two events: the primary-magmatic crystallization of PGM and later hydrothermal overprint.
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