Fluorapatiitti

Fluorapatiitti is a mineral belonging to the apatite group. Its chemical formula is Ca5(PO4)3F, indicating it is a calcium phosphate where fluoride ions substitute for hydroxyl or chlorine ions found in other apatites. It is a common mineral found in a wide variety of geological environments. Fluorapatiitti is often found in igneous rocks, particularly those rich in silica or alkaline in nature. It also occurs in metamorphic rocks and as a significant component of sedimentary rocks, especially phosphorites. Bone and tooth enamel in vertebrates are also composed of a biogenic form of fluorapatiitti, highlighting its biological importance.

This mineral typically appears as prismatic or acicular crystals, though it can also be found in massive or granular forms. Its color can vary widely, ranging from colorless and white to shades of yellow, green, brown, and even black, often due to trace impurities. Fluorapatiitti has a Mohs hardness of 5, making it relatively soft. It is insoluble in water but can be dissolved by strong acids. Its refractive index is approximately 1.63, and it exhibits moderate birefringence. Fluorapatiitti plays a role in various industrial applications, primarily as a source of phosphorus for fertilizers. It is also used in the production of ceramics, glass, and as a pigment.