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The sources of large and unique platinum-metal placers were the zonal alkali-ultrabasic massifs becoming active in the Cretaceous time that gravitated to the periphery of the areal of the North-Asian Superplume (NAS) influence. Origin of the conditions favorable for the formation of the placer platinum presence in the region is governed by the plume ore-generating magmatism of several generations (in Proterozoic and Phanerozoic). Ultramafite-mafite magmatism was responsible for the origin of the stratified zonal massifs subjected in the Late Paleozoic and Mesozoic to the action of granitogene derivations of the NAS. The latter provided the development of the ore-forming magmagene-fluid-metasomatic processes and favorable conditions for the platinum group elements concentration.