Granite

Igneous - plutonic

Granite is a plutonic or intrusive igneous rock formed by the slow cooling of magma at depth. The slow cooling allowed crystals of quartz, feldspar, biotite, and augite to grow fairly large. The Sierra Nevada batholith consists largely of granodiorite which has less quartz than granite, but looks very similar — "granite" is sometimes used as a generic word to describe this type of rock, but geologists have several different terms that describe the rock’s chemical composition.