Named as one of five formations of Libby Creek Group probably for Quartzite Peak, Carbon Co, WY, Northern Rocky Mountain region. No type locality designated. Consists of 1,000 m of massive vitreous white orthoquartzite. Very resistant to erosion. Forms distinctive outcrops along North Fork of Encampment River. The quartzite is clean and homogeneous except for a few translucent blue kyanite layers and muscovite zones. Lenticular quartz grains with irregular boundaries make up nearly 100 percent of the formation. Primary bedding and cross-bedding are rare. Conformably overlies Copper Creek Conglomerate (new) of Libby Creek Group. Underlies Slaughterhouse Marble (new), top formation of Libby Creek. Geologic map; mapped with all five formations of the Libby Creek Group. Columnar section. Assigned to the Proterozoic.

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