One of the most common intrusive rocks, granite has a total silica content above 65 percent and a minimum quartz content of 20 percent. K-feldspars (orthoclase and microcline) are normally dominant over plagioclase (Na-rich) feldspar and often pink. Mica occurs as dark biotite or as silvery muscovite. Hornblende may be present.

TEXTURE Granite is a coarse-grained rock with crystals larger than 3⁄16 in (5 mm) in diameter.

ORIGIN Forms at considerable depth in the Earth’s crust.

Origin: Intrusive

Grain size: Coarse

Crystal shape: Anhedral, Euhedral

Classification: Felsic

Occurrence: Pluton

Color: Light