- Cobaltoan Calcite on Calcite
- Small Cabinet, 8.1 x 4.8 x 4.2 cm
- Aghbar Mine, Bou Azzer District, Ouarzazate Province, Draa-Tafilalet, Morocco
- Ex. Tom Hall
Cobaltoan Calcites from Bou Azzer can rank among the world's finest. Basically dodecahedrons, these pink crystals fully cover one side of the matrix, with the largest crystals ranging to just over 1 cm. The faces of these modified Calcites vary from smooth and lustrous to very finely terraced, the combination of which creates a nice visual counterpoint. Interestingly, the Calcites grade from a lower layer of pure Calcite, as evidenced by the fluorescence, into the upper layer of Cobaltoan Calcite. This was not immediately obvious until looking under a UV light, and the effect is dramatic, almost like a fluorescent x-ray. Overall, this is an uncommonly good and aesthetic small cab from Bou Azzer.