Composition: PbZn2(AsO4)2.2H2O
Crystal System : Triclinic
Colours: Sky-blue
Lustre : Vitreous
Hardness (H) : 4.5
Specific Gravity (S.G) : 5.3
Year of Discovery: 1979
IMA Number: 1979-010
IMA Status: Approved
Discovered By: Gunther Schnorrer
Named for: Helmut Winkler (German Mineralogist)

Tsumeb is the Type Locality


Extremely rare. The level from which the type specimen was collected is not known.


  • Supergene
  • 2nd Oxidation Zone

Notable Finds

Gebhard (1999) reports that an early find was made on 30 Level, with adamite, and two other (then) new minerals, koritnigite and warikahnite. Keller and Bartelke (1982) describe a similar assemblage from the E9 Pillar on 31 Level, with willemite and quartz also present.

Paragenetic and General Notes

A member of the tsumcorite group, in corroded tennantite ore with willemite, and quartz.