( n. )
A variety of pyroxene, usually of a black or dark green color, occurring in igneous rocks, such as basalt; -- also used instead of the general term pyroxene.
( n. )
A variety of pyroxene, usually of a black or dark green color, occurring in igneous rocks, such as basalt; -- also used instead of the general term pyroxene.
Webster's Revised Unabridged English Dictionary. Пересмотренный полный словарь английского языка Webster. 2012