Cuprite , Conichalcite and Calcite
Tsumeb Mine, Namibia. 13mm x 35mm x 15mm.
Cuprite was a common mineral throughout the mine, although good quality examples are rare. The best find occured on the 12th level, as well as the 44th level, with specimens in the region of 4-5cm in size.
Good quality, crystalling Cuprite is very difficult to acquire, often commanding high prices internationally. This piece shows a well crystallized example of the species contrasting well with the white Calcite.
Cuprite presents itself in two varieties from Tsumeb - as we see it above, and as an acicular variety - Chalcotrichite, which is relatively rare and often responsible for red inclusions in Cerussite - Quite a famous combination. Malachite after Cuprite is the most common of the psuedomorphs, although Conichalcite and Plancheite are also known to replace Cuprite.
This specimen is associated with what is most likely Conichalcite, also on a bed of Calcite sitting on an ore matrix. Conichalcite is often confused with the other "green minerals" from Tsumeb - And is considered to form a series with Duftite. The mineral is found throughout the three oxidation zones, usually in a globular habit. Conichalcite is Orthorhombic, with psuedomorphs generally noted after Calcite, Chalcocite and Cuprite, all considered to be very rare.