Contemporaneous Segregation of PGE- and BM-Rich Sulfide Melts and Chromite Crystallization: The Caridad Chromite Deposit, Mayarí-Baracoa Ophiolitic Belt (Eastern Cuba)

An immiscible sulfide melt rich in platinum group elements (PGE) and base metals (BM) appears to have segregated contemporaneously with the crystallization of chromite during the formation of an ophiolitic chromitite body (Caridad deposit) in the Sagua de Tanamo mining district (eastern Cuba). Evidence includes: 1) droplet-like inclusions of BM sulfides in laurite (often oriented along growth planes); and 2) PGE- and BM-rich sulfide mineralogy now found as solid inclusions in the chromite. The segregation of immiscible sulfide melts coeval with chromite crystallization is explained in terms of chromitite formation by turbulent mixing/mingling of melts in open conduits in the upper sub-oceanic mantle.