Color is variable from iron-black to bluish black to steel gray. Luster is submetallic to dull in earthy specimens. Transparency crystals are opaque. Crystal System is monoclinic. Crystal Habits include massive, fibrous, botryoidal, columnar, stalactitic, concretionary, powdery and earthy.
Cleavage is absent.
Fracture is conchoidal to uneven. Hardness is 5 - 5.5. Streak is black or brownish black. Associated Minerals are barite , hematite , quartz , pyrolusite and other manganese oxide minerals. Best Field Indicators are habits, luster, hardness, color and streak.