3.2" Quartz and Calcite with Metacinnabar Inclusions - Cocineras Mine

This is a beautiful association of quartz and calcite crystals with metacinnabar inclusions that was collected from the Cocineras Mine in Chihuahua, Mexico.

Metacinnabar is a cubic form of mercury sulfide. While mercury sulfide is considered nonpoisonous, it still contains mercury and should be handled with care and kept away from children. We suggest washing your hands after handling specimens that contain mercury.

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.

Silicon Dioxide, also known as SiO2 or Quartz, is the second most abundant mineral in the Earth's crust. Quartz crystals generally grow in silica-rich, hot watery solutions called hydrothermal environments, at temperatures between 100°C and 450°C, and usually under very high pressure. Quartz veins are formed when open fissures are filled with hot water during the closing stages of mountains forming, and can be hundreds of millions of years old.

Quartz, Calcite & Metacinnabar
Cocineras Mine, Santa Eulalia Distract, Chihuahua, Mexico
3.2 x 1.8"