High- and low-temperature platinum nuggets from two historical localities, Chocó in Colombia and Córrego Bom Sucesso in Brazil, are compared with respect to trace elements. Supergene platinum nuggets from Córrego Bom Sucesso are enriched in Se and Hg, but depleted in siderophile and chalcophile elements, and have fractionated platinum group element patterns, in comparison with magmatic platinum nuggets from Chocó. In particular, Se concentrations over ~100 μg/g Se and S/Se ratios above unity indicate Se recycling in a supergene environment with abundant organic matter.

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