Dioptase - Mineral Specimen unique calcite this material is a rare

this material is a rare geological phenomenon

The overall look is dark and dramatic

These fractures were filled with hot hydrothermal fluid that had high quantities of silica

The crystals grew in open cavities within a hydrothermal system

typical of common to semi-precious opal material from these fields

Dioptase - Mineral Specimen unique calcite this material is a rareMined from: Renville Mine, Pool Department, Republic of the Congo Description: This dioptase specimen from the Renville Mine shows a classic botryoidal copper rich matrix coated with dense clusters of deep green crystals lining a natural cavity. The outer surface has that velvety, granular look typical of oxidized copper minerals, while the interior opens into a pocket of well formed, glassy dioptase crystals. The contrast between the rough exterior