Lexicon

Schist

Metamorphic rock usually derived from fine-grained sedimentary rock such as shale. Individual minerals in schist have grown during metamorphism so that they are easily visible to the naked eye. Schists are named for their mineral constituents. For example, mica schist is conspicuously rich in mica such as biotite or muscovite.

Indian Peaks - Schist rock

Schist comprises the oldest rock in the Indian Peaks Wilderness, Colorado.