Jamesonite , boulangerite and millerite are other sulfides that form similar acicular crystals. Zinkenite is a sulfosalt, a segment of sulfides where the antimony acts more like a metal than a non-metal and occupies a position where it is bonded to sulfurs. A variety of zinkenite from Tasmania contains a small amount of silver. Color is steel gray to gray. Luster is metallic.
Crystals are opaque.
Crystal Habits include dense or sparse felted masses of acicular crystals. Larger crystals show hexagonal prismatic and pyramidal forms. Streak is steel gray. Crystals are brittle. Associated Minerals include quartz, calcite, arsenopyrite , jamesonite , boulangerite and other sulfosalts.