Composition: PbGe4O9
Crystal System : Triclinic
Colours: Colourless, white
Lustre : Sub-adamantine
Hardness (H) : 3
Specific Gravity (S.G) : 5.77
Year of Discovery: 1978
IMA Number: 1978-080
IMA Status: Approved
Discovered By: Bruno H. Geier (Tsumeb mineralogist)
Named for: Otjitsume - the Herero word for Tsumeb
References: Keller et al. (1981a)

Tsumeb is the Type Locality


Extremely rare. Second oxidation zone.


  • Supergene
  • 2nd Oxidation Zone

Paragenetic and General Notes

As radiating groups of colourless needles to 1 mm, in chalcocite (Gebhard, 1999).

In the type specimen otjisumeite needles are intergrown with siderite (older) and schaurteite (younger) (Keller & Bartelke, 1982).

Otjisumeite forms pseudo-hexagonal crystals that can readily be confused with willemite needles.