Sopcha lake chromite deposit and its platinum potential, Monchegorsk Pluton, Kola Peninsula (Russia)

A chromium deposit was found in the southwestern part of the Monchegorsk ni ckel-bearing pluton. The sheet-shaped chromite lode is confined to dunites located in the middle part of the section of the Monchegorsk Pluton. The du nites and chromite ores exhibit elevated platinum-group element (PGE) conce ntrations. There is a positive correlation of Pt and Pd with S and Ph with Cr. The origin of the chromite horizon with elevated PGE contents is accoun ted for the mixing of two magmas: (1) a highly evolved magma with crystalli zing plagioclase, and (2) a new portion of primitive magma bearing sulfides enriched in PGE, Both magmas were derived from the same intermediate magma chamber.