Plumbogummite


Composition:

PbAl3(PO4)(PO3OH)(OH)6

Crystal System : Trigonal
Colours: Light blue, gray-white, yellow-gray, yellow, yellow-brown, red-brown, greenish, bluish, dark blue-gray;
Lustre : Greasy
Hardness (H) : 4.50-5.0
Specific Gravity (S.G) : 4.01

 

Distribution

Extremely rare.

Occurrence

  • Supergene

Paragenetic and General Notes

Mills et al. (2009) described gallium-rich plumbogummite from Tsumeb. Subsequently, Schlüter and Malcharek (2011) and Schlüter et al. (2014) described galloplumbogummite as a new species from Tsumeb.

A germanium-bearing plumbogummite has been provisionally identified but further work is required (Joy Desor, 2014, personal communication to M. Southwood) and for this reason it is appropriate that plumbogummite remains on the Tsumeb species list. The germanium-bearing phase occurs with bartelkeite and fleischerite in tiny vugs in germanium-rich massive sulphide.