Staurolite

Staurolite is nesosilicate mineral. Its crystal is monoclinic system’s nesosilicate mineral, and generally coarse, short columnar, brownish red, reddish brown, yellowish brown or black, glassy. Morse hardness is 75. Specific gravity is 3.74 ~ 3.83. It is named for its strange cross shape. Staurolite is hard and crisp, with a dull luster, generally dark brown. Staurolite is the product that the argillaceous rocks rich in iron, aluminum have gone through the regional metamorphism. It is usually found in mica schist, phyllite, gneiss, and is a typical medium degree of regional metamorphic mineral.