Gabbro | Encyclopedia
gabbro A coarse-grained, basic igneous rock, consisting of essential calcium-rich plagioclase feldspar (approximately 60%), clinopyroxene (augite or titanaugite), and orthopyroxene (hypersthene or bronzite), plus or minus olivine with accessory magnetite or ilmenite.Gabbros result from the slow crystallization of magmas of basaltic composition, …