Composition: Pb5Si4O8(OH)10
Crystal System : Orthorhombic
Colours: Colourless, white
Hardness (H) : 2
Year of Discovery: 1979
IMA Number: 1979-049
IMA Status: Approved
Discovered By: Wolfgang Bartelke (German collector)
Named for: Composition/locality

Tsumeb is the Type Locality


Extremely rare. Second oxidation zone.


  • Supergene
  • 2nd Oxidation Zone

Notable Finds

A number of specimens from the major alamosite discovery of the mid-1970s, included plumbotsumite as an accessory mineral.

Paragenetic and General Notes

Plumbotsumite occurs in small vugs on the terminations of alamosite crystals, with melanotekite.

As colourless aggregates of cleaved grains, or of tabular pseudo-hexagonal crystals to 0.5mm.  Rarely as larger crystals and crystal aggregates, forming a matrix for sprays of alamosite crystals.