apatiit

Apatite is a group of phosphate minerals, usually referring to hydroxylapatite, fluorapatite, and chlorapatite, with high concentrations of OH-, F- and Cl- ions, respectively, in the crystal. The formula of the admixture of all members of the group is Ca5(PO4)3(OH, F, Cl). Apatite is one of the most abundant minerals in the Earth's crust. It is a major constituent of tooth enamel and bone mineral. Apatite is also a significant ore of phosphorus, which is a key component in fertilizers and other industrial applications.

Apatite is typically found in igneous, metamorphic, and sedimentary rocks. It can occur as large, well-formed crystals or as fine-grained masses. The color of apatite can vary widely, including colorless, yellow, green, blue, purple, and black. The most common form is fluorapatite, which is often found in the form of hexagonal crystals.

Apatite has several industrial uses. It is a source of phosphorus, which is used in the production of fertilizers, phosphoric acid, and phosphate salts. It is also used in the production of glass and ceramics, as a filler in plastics, and as a component in toothpaste and other dental products. Apatite is also used in the production of high-temperature ceramics and as a flux in metallurgy.

Apatite is also of geological interest. It is often found in association with other minerals, such as calcite, fluorite, and quartz. It can also be found in hydrothermal veins and in pegmatites. Apatite is also a common constituent of meteorites, and it has been found in lunar samples.