This Specimen has been sold.
4.4" Calcite Crystal Cluster - Morocco
This is an aggregation of calcite crystals that were collected from the Oumjrane area of Morocco. Small pyrite crystals can be found scattered throughout the specimen. Under short wave UV, these crystals fluoresce orange.
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.