It is usually associated with the colorful limonite , an iron oxide, and the combination can make for a nice cabinet specimen. Color is colorless and pale white, red, green, yellow or brown. Luster is vitreous. Transparency crystals are transparent to translucent. Crystal System is triclinic, bar 1 Crystal Habits include deeply striated prismatic crystals or crusts.
Cleavage is perfect in one direction.
Streak is white. Associated Minerals are limonite , smithsonite and some other oxidized zinc ore deposit minerals. Notable Occurrences include Broken Hill, Shaba, Zambia and elsewhere.