PYROXENE

Photo shows diopside (CaMgSi2O6), a member of the pyroxene group.

Chemical Composition: XY(SiO3)2 where X=Y=Ca, Mg, Fe

Hardness: 5-6

Color: dark green to black (augite); white to green

Specific Gravity: 3.2-3.9

Cleavage Planes: two, perfect, nearly at right angles

Crystal Structure: 8-sided stubby crystals

Luster: nonmetallic

Other Properties: igneous and metamorphic rocks