First published use as a map unit. Is in a stock or neck which in its southern part broke across the outer part of a volcanic cone, the center of which can be seen on Volcano Ridge. Occurs as a widespread unit in the southern part of the quad, Juab Co, UT in the Great Basin province, and as a smaller exposure near the east central border of the quad in Utah Co, UT on the Wasatch uplift. Sunbeam mine is in T10S, R2W. Intent to name, source of name [probably the Sunbeam mine in T11S, R2W], and type locality not stated. The monzonite and monzonite porphyry described as porphyritic; groundmass is holocrystalline and granular. Chemical analyses. Geologic map. Shown as Tertiary age, younger [?] than Tintic andesite.

Source: GNU records (USGS DDS-6; Denver GNULEX).