Glaucophane is a blue mineral commonly found in metamorphic rocks. It is a member of the amphibole group of minerals and is composed of sodium, magnesium, iron, aluminum, silicon, and oxygen. Synonyms for the word glaucophane include blue asbestos, blue jadeite, and blue hornblende. These minerals share some similarities with glaucophane but differ in their chemical composition and crystal structure. Blue asbestos, for example, is a type of fibrous mineral that was used in insulation materials but is now banned due to its health risks. Blue jadeite, on the other hand, is a gemstone used in jewelry, while blue hornblende is a mineral commonly found in igneous rocks.