Dioptase on Calcite is one of the most attractive and desirable of all the Tsumeb combinations. These Dioptases are gemmy, a rich emerald green, and super lustrous. Much more so than the pics can portray, in fact. The largest of these crystals just reaches 1 cm, and they all rest on a bed of gemmy Calcite rhombs that average 2-3 mm. Both generations of Calcite are fluorescent. Tsumeb, of course, is long closed, and this highly representative piece is aesthetic, and big for the price.