Calcite and dioptase specimens are very highly desirable from the Tsumeb Mine. This is a striking and aesthetic combination specimen of the two species. A showy cluster of sharp, glassy calcite rhombs to 1.6 cm have a thin veneer or are included by dioptase microcrystals. Festooned atop the green-tinted calcite rhombs is a sparkling, second generation of sugary calcite crystals, which really add a dramatic effect to this excellent specimen. Very nearly pristine. Ex. Al and Sue Liebetrau Collection.