This Specimen has been sold.
8.5" Free-Standing Rainbow Calcite Display - Durango, Mexico
This is a mass of rough rainbow calcite that was collected from Durango, Mexico. It is 8.5" wide and the base has been cut flat for presentation purposes. This specimen features layered red and green calcite.
Calcite, CaCO3, is a carbonate mineral and the most stable polymorph of calcium carbonate. The other polymorphs are the minerals aragonite and vaterite. Calcite crystals are trigonal-rhombohedral, though actual calcite rhombohedra are rare as natural crystals. However, they show a remarkable variety of habits including acute to obtuse rhombohedra, tabular forms, and prisms. Calcite exhibits several twinning types adding to the variety of observed forms. It may occur as fibrous, granular, lamellar, or compact. Cleavage is usually in three directions parallel to the rhombohedron form.