Dacite

Dacite is an igneous, volcanic (extrusive) rock, of felsic composition, with aphanitic to porphyritic texture. Mineral assembly is usually quartz, alkali feldspar and plagioclase (in a ratio < 1:2). Quartz and alkali feldspars may be scarce. Biotite, hornblend and pyroxene are common accessory minerals.

See also: igneous rocks, list of rocks