Mineral Species
plumbogummite
Type Locality
No
Composition
PbAl3(PO3.5(OH)0.5)2(OH)6
Crystal System
Trigonal
Status at Tsumeb
Confirmed
Abundance
Extremely rare
Distribution
Second oxidation zone
Paragenesis
Supergene
Entry Number
Species; TSNB281
General Notes
The first formal recognition of plumbogummite at Tsumeb was by Mills et al. (2009) who described a gallium-rich variety of the mineral as transparent white single rhombohedral crystals (to 300 µm) on gallite-renierite-germanite ore. Ga-rich plumbogummite occurs with an unnamed Ga analogue of arsenocrandallite (from which it is visually indistinguishable).
A germanium-bearing plumbogummite has been provisionally identified but further work is required for full characterisation (Joy Désor, 2014, pers. comm. to M. Southwood). The germanium-bearing phase occurs as minute spherical aggregates with bartelkeite and fleischerite in tiny vugs in germanium-rich massive sulphide ore.
