Dioptase

Dioptase was first documented and named by Rene Just Hauy (1743-1822), a french mineralogist and founding father of crystallography. His law of rational proportions for crystal angles and his classification of crystals into six systems in his Treatise on Crystallography (1822), were the launch pad for many further discoveries in crystallography. 
 
Dioptase forms as a secondary mineral in copper deposits and is created by the weathering and oxidation of primary minerals in limestone or calcite formations. It is often associated with other secondary copper minerals such as malachite, chrysocolla and azurite. 
 
The formation of dioptase requires warm and dry conditions, hence it is mined in arid places.
 
Weight: 26g
Dimensions: 4cmx4cmx1cm