Detailed information
Species
Mottramite
Dimensions
105 x 85 x 55
mm
Weight
138 g
Locality
Tsumeb Mine Tsumeb, Oshikoto Region Namibia
Condition
No recorded repairs
This is a really funky oddity known only from the famous Tsumeb mine. Mottramite is ordinarily a very rare lead copper vanadate species but at Tsumeb mine it occurred in several different forms, some of which are extremely rich. This really intriguing specimen is an apparent cast of Mottramite after some unknown mineral, or minerals. It is a large, cabinet-sized boxwork of thin 'sheets' of murky to khaki-green Mottramite crystals interlocking with large hollow open spaces. This open texture is more commonly seen with Smithsonite in limestone deposits and may well represent a metasomatic replacement of Mottramite after dolomitized limestone resulting in this change in volume. It really is a weird and wonderful example of the complex geochemistry which went on in the orebodies at Tsumeb mine. Ex Weyand collection.