3.3 x 1.8 x 1.1 cm. Cyan-blue, microcrystalline Stranskiite highlights this specimen. The largest portion of Stranksiite is nearly 8 mm long, and the mineral is actually translucent. Stranskiite is a very rare zinc arsenate and Tsumeb is the Type Locality. For what it is, this Stranksiite miniature is superb. Locality: Tsumeb Mine, Tsumeb, Otjikoto Region, Namibia — Photo: Robert M. Lavinsky · CC BY-SA 3.0
Stranskiite
Stranskiite is an IMA-recognized mineral species in the arsenate class, with the chemical formula CuZn₂(AsO₄)₂.
It crystallizes in the triclinic crystal system (space group P-1).
Key properties: Mohs hardness 4; specific gravity 5.23–5.3; Vitreous luster; optically biaxial.
IMA symbol Ssk, IMA status: approved, named in 1960.
A very rare secondary mineral found in the oxidized zone of a dolostone-hosted hydrothermal polymetallic ore deposit.
It is found associated with Chalcocite, tennantite, galena, schulténite, anglesite, bayldonite, cuprian adamite, keyite, olivenite, claudetite, ludlockite, tsumcorite, koritnigite.
The mineral was named to honor Professor Iwan N. Stranski (1897–1979), German chemist and physicist, Berlin, Germany.