Color is black, greenish black, dark green and dark brown. Luster is vitreous to dull. Transparency crystals are translucent to opaque. Good crystals are rare, more commonly compact, granular, lamellar and massive. Cleavage is perfect in two lengthwise directions at close to right angles and a basal parting direction is sometimes seen.
Fracture is uneven to conchoidal.
Streak is white to pale green. Associated Minerals are wollastonite , grossular , andradite , magnetite , actinolite , galena , rhodonite and calcite . Best Field Indicators are crystal habit, associations, color, fracture and cleavage.