FERROAN CALCITE with CHABACITE-Ca

Chabazite is a tectosilicate mineral belonging to the zeolite group, closely associated with gmelinite, and has the chemical formula (Ca,K2,Na2,Mg)Al2Si4O12•6H2O. It includes recognized varieties such as Chabazite-Ca, Chabazite-K, Chabazite-Na, and Chabazite-Sr, which are distinguished by the dominant cation present.

This mineral crystallizes in the triclinic system, typically forming pseudo-cubic, rhombohedral-shaped crystals that often exhibit twinning, including both contact and penetration types. Chabazite can appear in various colors, including colorless, white, orange, brown, pink, green, or yellow. Its hardness ranges from 3 to 5, with a specific gravity between 2.0 and 2.2, and it possesses a vitreous luster.

Ferroan Calcite is iron-bearing calcite. 

Calcite is a carbonate mineral and the most stable form of calcium carbonate (CaCO3). It is widely found, especially as a key element in limestone. With a hardness rating of 3 on the Mohs scale, calcite is assessed based on its ability to be scratched. Large crystals of calcite are utilized in optical devices, while limestone, primarily made up of calcite, serves a variety of purposes.

This specimen of ferroan calcite reacts to Long Wave UV and is also phosphorescent (VIDEO).

The associated mineral is chabazite-Ca and can be found on the base and on some calcite crystals. This specimen is one of the most exceptional ones from this locality and extremely rare.