Dioptase
“Emerald-green copper crystals”
Dioptase is a vivid emerald-green copper cyclosilicate mineral that forms stunning prismatic crystals in the oxidation zones of copper deposits. When first discovered, it was mistaken for emerald due to its intense color, and it remains one of the most photogenic minerals in any collection.
copper cyclosilicate (CuSiO₃·H₂O)
Tsumeb (Namibia), Mindouli (Republic of Congo), Altyn-Tyube (Kazakhstan — type locality), Renéville (Congo), Arizona (USA)
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French mineralogist René Just Haüy named dioptase from the Greek words meaning 'to see through' because he could see the internal cleavage planes through the transparent green crystal faces.
Test Your Knowledge
Why was dioptase initially mistaken for emerald upon its discovery?
Photo Attribution
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