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Reinerite

Reinerite
General
Category arsenite
Formula
(repeating unit)
Zn3(AsO3)2
Strunz classification 4.JA.10
Crystal system Orthorhombic
Crystal class Dipyramidal (mmm)
H-M symbol: (2/m 2/m 2/m)
Unit cell a = 6.092 Å, b = 14.407 Å
c = 7.811 Å; Z = 4
V = 685.55
a:b:c = 0.423 : 1 : 0.542
Identification
Color Sky blue, yellow green
Crystal habit Rough striated pseudohexagonal crystals
Cleavage Good on {110}, {011} and {111}
Mohs scale hardness 5 - 5.5
Luster Vitreous to adamantine
Diaphaneity Transparent
Specific gravity 4.27
Optical properties Biaxial (-)
Refractive index nα = 1.740 nβ = 1.790 nγ = 1.820
Birefringence Maxium δ = 0.080
References

Reinerite is a rare arsenite (arsenate(III)) mineral with chemical formula Zn3(AsO3)2. It crystallizes in the orthorhombic crystal system.

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.

Reinerite develops in dolostone-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, 800 m (2,600 ft) below the surface, in the second oxidation zone. It occurs in association with chalcocite, bornite, willemite, smithsonite, hydrozincite, hemimorphite, adamite, olivenite and gebhardite.

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.


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