DIOPTASE
Specimen dio-10
$ 80.00Dims: 1.6" x 1.5" x 1.1" (4.1 x 3.8 x 2.8 cm)
Wt: 1.86 oz. (52.8 g)
Altyn-Tube, Kirghese Steppes, Kazakhstan
A crust made up of dozens of Dioptase crystals partially covers a pale brown host rock that I think is made of chert or a similar silicate material. The crystals that make up the crust are generally in very good condition, as damage is limited to the crust's edges. The largest of these crystals has dimensions of 0.4 x 0.1 x 0.1" (1.0 x 0.3 x 0.3 cm) and is incomplete due to heavy intergrowth. All have good trigonal rhombic-based form and well-defined edges and smooth faces that show a vitreous luster. Their color is the intense, deep emerald-green that is the main characteristic of Dioptase, and the crystals are transparent, though all are marred by considerable internal fracturing.