Composition: Zn2Cu2+(AsO4)2
Crystal System : Triclinic
Colours: Cyan-blue, white
Lustre : Vitreous, sub-vitreous, dull
Hardness (H) : 4
Specific Gravity (S.G) : 5.23
Year of Discovery: 1960
IMA Number: 1962 s.p.
IMA Status: Approved
Discovered By: Hugo Strunz (German mineralogist)
Named for: Iwan N. Stranskii (German scientist)
References: Strunz (1960a)

Tsumeb is the Type Locality


Very rare. Second and third oxidation zones.


  • Supergene
  • 2nd Oxidation Zone
  • 3rd Oxidation Zone

Paragenetic and General Notes

The type specimen for stranskiite is from 30 Level, in the second oxidation zone, where stranskiite occurs on chalcocite as tabular crystals in radiating aggregates to 10 mm, and also in massive form. The colour is cyan-blue, and the crystals are vitreous and semi-transparent.

In 1994, stranskiite was discovered in the third oxidation zone, on 44 Level, as 2 mm sprays of white crystals on a blue unknown (GS 3 of Gebhard; Gebhard, 1999).

Gebhard (op. cit.) suggests that the blue colour of the original stranskiite find may be atypical and that white stranskiite (as found in the third oxidation zone) may be more common.