This Specimen has been sold.
Unusual 4.4" Dogtooth Calcite Crystal - Morocco
This is an unusual shaped dogtooth calcite crystal collected from Morocco. This crystal is 4.4" tall, and has a brown-yellow coloration. The crystal has stress fractures that likely give the crystal its curved shape, however there is little damage to its termination.
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.