How do I identify Hydroxylapatite?

Hydroxylapatite can be identified by its hardness of 5 on the Mohs scale, White color. Look for these key characteristics when examining specimens.

What color is Hydroxylapatite?

Hydroxylapatite typically appears in White, grey, yellow, green, violet, purple, red or brown. Color can vary depending on impurities and formation conditions.

How hard is Hydroxylapatite?

Hydroxylapatite has a hardness of 5 on the Mohs scale. This gives it moderate hardness.

Hydroxylapatite

A variety of Minerals

What is Hydroxylapatite?

Hydroxyapatite, also called hydroxylapatite (HA), is a naturally occurring mineral form of calcium apatite with the formula Ca5(PO4)3(OH), but it is usually written Ca10(PO4)6(OH)2 to denote that the crystal unit cell comprises two entities. Hydroxyapatite is the hydroxyl endmember of the complex apatite group. The OH ion can be replaced by fluoride, chloride or carbonate, producing fluorapatite or chlorapatite. It crystallizes in the hexagonal crystal system. Pure hydroxyapatite powder is white. Naturally occurring apatites can, however, also have brown, yellow, or green colorations, comparable to the discolorations of dental fluorosis. Up to 50% by volume and 70% by weight of human bone is a modified form of hydroxyapatite, known as bone mineral. Carbonated calcium-deficient hydroxyapatite is the main mineral of which dental enamel and dentin are composed. Hydroxyapatite crystals are also found in the small calcifications, within the pineal gland and other structures, known as corpora arenacea or 'brain sand'.

Uses & Applications

In archaeology, hydroxyapatite from human and animal remains can be analysed to reconstruct ancient diets, migrations and paleoclimate. The mineral fractions of bone and teeth act as a reservoir of trace elements, including carbon, oxygen and strontium. Stable isotope analysis of human and faunal hydroxyapatite can be used to indicate whether a diet was predominantly terrestrial or marine in nature (carbon, strontium); the geographical origin and migratory habits of an animal or human (oxygen, strontium) and to reconstruct past temperatures and climate shifts (oxygen). Post-depositional alteration of bone can contribute to the degradation of bone collagen, the protein required for stable isotope analysis.

Hydroxylapatite Market Value Calculator

Estimate the market value of Hydroxylapatite using size, quality, and finish. This preview calculator is for quick context and is not a formal appraisal.