Composition: Pb3Ge4+(SO4)2(OH)6.3H2O
Crystal System : Hexagonal
Colours: White, very pale pink
Lustre : Sub-vitreous, silky
Hardness (H) : 2.5-3.0
Specific Gravity (S.G) : 4.55
Year of Discovery: 1957
IMA Number: 1962 s.p.
IMA Status: Approved
Discovered By: Clifford Frondel and Hugo Strunz (American and German mineralogists respectively)
Named for: Michael Fleischer

Tsumeb is the Type Locality


Very rare. The type material is from the first oxidation zone, between 6 and 8 levels. Also found in the second oxidation zone, on 35 Level.


  • Supergene
  • 1st Oxidation Zone
  • 2nd Oxidation Zone

Notable Finds

The type assemblage comprises tennantite, mimetite, plumbojarosite and quartz. On 35 Level fleischerite was found "growing through" crystals of anglesite and associated with melanotekite and kegelite.

Paragenetic and General Notes

The first germanium sulphate described and, surprisingly, found in a part of the ore body dominated by secondary carbonates. Can be confused with dundasite, with schaurteite (itself a Ge sulphate), and possibly with biehlite. The type specimen occurrs on tennantite, with cerussite, mimetite, plumbojarosite and dolomite.

The type specimen was acquired by Harvard University in 1953 and is believed to be one of the key specimens that persuaded Professor Clifford Frondel (then curator at Harvard) to purchase the collection of Wilhelm Klein a mine captain at Tsumeb between 1916 and 1939 (Carl Francis, personal communication to M.Southwood, 2015).

The following minerals are reported to form pseudomorphs after fleischerite:  itoite (rare, Weber (1977), doubtful status).