Dioptase with Calcite

Unknown Owner

Attractive emerald green crystals of dioptase measuring to 0.3 cm in size across the front of matrix with rhombohedral crystals of calcite. Attractive and in good condition.The Tsumeb Mine in Namibia is one of the most famous polymetallic deposits in the world, with large scale mining beginning around 1905 and continuing until its closure in 1996. The deposit is a complex pipe like ore body hosted in dolomitic limestone and is exceptionally rich in copper, lead, zinc, and many rare elements. Extensive underground workings reached great depths and produced an extraordinary variety of minerals, especially in the oxidized zones where secondary mineralization developed. Among the most notable minerals from Tsumeb is dioptase, a copper silicate that occurs as bright emerald green crystals often forming well defined rhombohedral shapes. These crystals formed in open cavities where copper rich solutions interacted with silica under favorable conditions, producing some of the finest and most vivid dioptase specimens known from any locality.