Metazeunerite

Metazeunerite
Metazeunerite crystals to 7 mm on smoky quartz, Erongo Region, Namibia
General
CategoryPhosphate minerals
FormulaCu(UO2)2(AsO4)2·8H2O
IMA symbolMzeu
Strunz classification8.EB.10
Crystal systemTetragonal
Crystal classDipyramidal (4/m)
(same H-M symbol)
Space groupP4/n
Unit cella = 7.1094 Å, c = 17.416 Å;
Z = 2
Identification
ColorVaries from pale to green
Crystal habitTabular rectangular crystals with two pinacoid faces; foliated or micaceous aggregates
TwinningMerohedrally twinned
CleavagePerfect on {001}; distinct on {010}
FractureUneven
TenacityBrittle
Mohs scale hardness2–2.5
LusterVitreous to dull
StreakPale green
DiaphaneityTransparent to translucent
Specific gravity3.87
Optical propertiesUniaxial (−)
Refractive indexnw = 1.643–1.651 nε = 1.623–1.635
Birefringence.020
PleochroismWeak
SolubilitySoluble in acids
Other characteristics Radioactive,
Relief: moderate
References

Metazeunerite is an arsenate mineral with a chemical formula of Cu(UO2)2(AsO4)2·8H2O. The origin of this mineral is almost always from the natural dehydration process of zeunerite.

It is named for civil engineer Gustav A. Zeuner, who worked at the School of Mines in Freiberg and its lowered hydration state.