Natural Calcite — Raw

Calcite is a calcium carbonate with the chemical formula CaCO₃, being one of the most abundant minerals in the Earth's crust. It forms in a wide variety of geological environments: sedimentary rocks such as limestone and marble, caves by precipitation of aqueous solutions rich in calcium, hydrothermal veins and as a secondary mineral in igneous and metamorphic rocks. Its color is extremely variable — white, yellow, orange, pink, green, blue or colorless — determined by the presence of impurities and ionic substitutions in the crystalline structure, such as manganese, iron, zinc and cobalt. It presents perfect rhombohedral cleavage in three directions, a diagnostic characteristic of the species, in addition to marked birefringence in transparent specimens. Hardness: 3 on the Mohs scale. Density: 2.71 g/cm³. Crystalline system: trigonal. Available variations, approximate data: 1 to 3 cm — Approx. 0.010 kg — 250 pcs per kg 3 to 6 cm — 0.030 to 0.150 kg — 30 pieces per kg 6 to 15 cm — 0.150 to 0.800 kg — 2 to 3 pieces per kg