Title
zincgartrellite
Composition
Pb(Zn,Fe,Cu)2(AsO4)2(H2O,OH)2
Crystal System
Triclinic
Status at Tsumeb
Confirmed
Abundance
Very rare
Distribution
Second (?) and third (?) oxidation zones.
Paragenesis
Supergene.
Type Locality
Yes
Entry Type
Species TSNB380
Type Mineralogy
Zincgartrellite was discovered on specimens mined during the period 1975-1980 and purchased in Namibia by German mineralogist, Gerd Tremmel (1940-2020). Zincgartrellite, IMA 1998-014, was described by Effenberger et al. (2000); it is isostructural with gartrellite, compositionally similar to helmutwinklerite and a member of the tsumcorite group of minerals. The level of the mine from which the type material originated is not known. Type material is conserved at the Institut für Mineralogie, Ruhr-Universität Bochum, Germany (catalogue number 081).
General Notes
Zincgartrellite forms aggregates (to 0.5 mm) composed of tiny yellow-green crystals of tabular habit (to 100 μm). The individual crystals are intensely intergrown which hampers the accurate determination of physical and optical properties.
On the type specimen, zincgartrellite occurs on chalcocite, with duftite, wulfenite, olivenite and zincolivenite (Effenberger et al. 2000). It has also been observed as encrustations of minute, bright-yellow, tabular crystals (<0.1 mm), associated with zincolivenite and quartz, on silicified and mineralised dolostone.
As with most species in the tsumcorite group, analytical verification is necessary for the reliable identification of zincgartrellite.
Associated Minerals
chalcocite; duftite; olivenite; wulfenite; zincolivenite
