Title
plumbogummite
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.
Type Locality
No
Entry Type
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.
Associated Minerals
bartelkeite; chlorargyrite; corkite; fleischerite; gallite; germanite; krieselite; libethenite; otjisumeite; renierite; stottite; tsumebite
