Garnet
an isometric transparent or translucent brittle mineral, with dodecahedral cleavage, sometimes with twin crystals, having an octahedral composition face. It occurs also massive and . Color, red, brown, yellow, white, or black, with a white streak.
There are three leading varieties: (1) Alumina garnet, in which the sesqui- GARONNE oxide is mainly alumina; (2) Iron garnet, in which it is chiefly sesquioxide of iron; and (3) Chrome garnet, in which it is principally sesquioxide of chrome. Under these are ranked grossularite, pyrope, almandite, spessartite, andradite, bredbergite, and ouvarovite.