Fluorapatite, often with the alternate spelling of fluoroapatite, is a phosphate mineral with the formula Ca5(PO4)3F (calcium fluorophosphate). Fluorapatite is a hard crystalline solid. Although samples can have various color (green, brown, blue, yellow, violet, or colorless), the pure mineral is colorless, as expected for a material lacking transition metals, it can be a component of tooth enamel , but for industrial use both minerals are mined in the form of phosphate rock , whose usual mineral composition is primarily fluorapatite but often with significant amounts of the other.
Fluorapatite crystallizes in a hexagonal crystal system. It is often combined as a solid solution (Ca5(PO4)3OH or Ca10(PO4)6(OH)2) in biological matrices. Chlorapatite Industrially, the mineral is an important source of both phosphoric and hydrofluoric acids.
Fluorapatite as a mineral is the most common phosphate mineral. It occurs widely as an accessory mineral in igneous rocks and in calcium rich metamorphic rocks. It commonly occurs as a detrital mineral in sedimentary rocks and is an essential component of phosphorite ore deposits. It occurs as a residual mineral in lateritic soils
Fluorapatite is found in the teeth of sharks and other fishes in varying concentrations. It is also present in human teeth that have been exposed to fluoride ions, for example, through water fluoridation or by using fluoride-containing toothpaste. The presence of fluorapatite helps prevent tooth decay or dental caries Fluoroapatite has a critical pH of 4.5, thus it makes tooth structure more resistant to additional caries attack. It has a mild bacteriostatic property as well, which helps decrease the proliferation of Streptococcus mutans , the predominant bacterium related to dental caries.