A group of igneous and plutonic rocks composed primarily of feldspar and quartz. Usually contains one or more dark minerals, which may be mica, pyroxene, or amphibole. Granite is quarried for building stone, road gravel, decorative stone, and tombstones. Common colors are gray, white, pink, and yellow-brown.
Toughness; the quality of having a thick skin or being rough.
Rock or other material that contains valuable or utilitarian materials; primarily a rock containing metals or gems for which it is typically mined and processed.