The enigmatic botryoidal nuggets of platinum (Pt) and palladium (Pd) from Córrego Bom Sucesso in the southern Serra do Espinhaço, Minas Gerais, Brazil, are considered to have formed during supergene alteration placer deposits. This requires hitherto unidentified precious-metal enrichment processes is inconsistent with Pt–Os age 180 Ma that entails formation at depth, as recently proposed. Here ...