Dioptase on Calcite  Tsumeb Mine, Tsumeb, Otjikoto Region, Namibia.  Ex. Thomas G. Fowler collection.  A pretty example that stands on edge for display and measures 5.2 x 4.2 x 2.5 cm.  Deep green, lustrous, and transparent crystals.  Some crystals at base and one edge are damaged.  $270