Biotite gneiss and schist with garnet
Gneiss, schist & quartzite. Paleoproterozoic, about 2,500 to 1,600 million years old. 1 crag on this site has its map point on it.
What the map says
Gray, fine- to medium-grained, well-foliated gneiss composed chiefly of quartz, plagioclase, and biotite; garnet crystals in some layers as large as 1 cm in diameter. Locally schistose and contains muscovite. Mapped in western Morrison 7.5-minute quadrangle (Scott, 1972) and northern Indian Hills quadrangle (Bryant and others, 1973)
1:100,000 sheet: Kellogg and others, 2008, USGS Geologic Investigations Series 3000 (1 crag). A contact line at that scale is about 100 m wide on the ground.
Served by Macrostrat (CC BY 4.0). The wording is the map's own, quoted as a fact about the mapped unit, not about any one wall.