Reinerite

Reinerite is a rare arsenite (arsenate(III)) mineral with chemical formula Zn3(AsO3)2. It crystallizes in the orthorhombic crystal system.
Physical properties.
Reinerite is most commonly found as a sky blue colored mineral, however, it may also be a light yellowish green color. Reinerite has a relative hardness of 5 to 5.5 on the Mohs Scale which is equivalent to that of a knife blade and or shard of glass. It has a density of 4.27 g/cm3, and it exhibits a nonmetallic luster that may be described as glassy or vitreous.
Environment.
Reinerite develops in dolomite-hosted locations. It is known especially from Namibia, Africa, within the mines of Tsumeb. At the Tsumeb location, Reinerite develops within the polymetallic lead-zinc-copper deposit, below the surface, in the second oxidation zone. It occurs in association with chalcocite, bornite, willemite, smithsonite, hydrozincite, hemimorphite, adamite, olivenite and gebhardite.
History.
Reinerite was first described in 1958 for an occurrence in the Tsumeb Mine, Tsumeb, Namibia and named for senior chemist Willy Reiner (1895–1965) of Tsumeb Corporation, who analyzed this mineral.