Dioptase with Mottramite on Calcite

This combination is highly valued for its striking color contrast—the bright green dioptase and the greenish-yellow mottramite create a visually stunning effect, especially when the minerals are well-formed.   The fibrous nature of mottramite and the crystalline shapes of dioptase create an aesthetically pleasing structure, while the calcite provides balance and symmetry.

Dioptase and mottramite are both copper-bearing minerals, and they typically form in copper-rich environments, especially in areas with significant hydrothermal activity.   The presence of arsenic in mottramite and cobalt in dioptase helps to explain their association in certain geological settings.The presence of calcite in these specimens is often the result of secondary mineralization in the same hydrothermal system, where calcite precipitates out of the mineral-rich waters to form a matrix for other minerals to grow on.