Platinum content of sulphidic copper-nickel: ores in intrusive mafite-ultra-mafites of the Volynian megablock of the Ukrainian Shield was studied for the first time. It is found that accumulation of platinoids is a result of residual melts at high activity of bismuth and tellurium. A rise in the platinum concentration of minerals corresponds to an increase in metallic properties of relations in their structures. Attribution of platinoid concentration to zones of enhanced content of a volatile constituent of the ore-magmatic system may serve as a prospecting criterion.