Includes coarse-grained gabbro, diabase and altered equivalents which locally are garnet-glaucophane rocks.
glaucophane in Science
(glou'kə-fān') A blue to grayish-blue or bluish-black monoclinic mineral of the amphibole group. Glaucophane occurs as fibrous prisms in schists (especially blueschists) formed by the regional metamorphism of sodium-rich rocks. Chemical formula: Na2(Mg,Fe)3Al2Si8O22(OH)2.