Allanite pegmatites, Red Rock, Nevada compared with allanite pegmatites in southern Nevada and California

Small irregularly shaped aplitic allanite pegmatite bodies occurring near the contacts of a larger aplitic body with granodiorite are described. Allanite represents a considerable part of the pegmatite, is equally distributed, and can be regarded as a major constituent. Similar allanite pegmatites recently discovered in the Precambrian gneisses and schists in Clark County, Nevada, and San Bernardino County, California, are described in short. Typical characteristics of allanite pegmatites in general are given. In view of the abundance of the Precambrian rare earth deposits, it is suggested that this Precambrian area may represent a characteristic rare-earth province.