Properties
| Category | Phosphate mineral |
|---|---|
| Formula | Ca5(PO4)3(F,Cl,OH) |
| Crystal system | Hexagonal |
| Color | Transparent to translucent, usually green, less often colorless, yellow, blue to violet, pink, brown. |
| Crystal habit | Tabular, prismatic crystals, massive, compact or granular |
| Cleavage | indistinct, indistinct |
| Fracture | Conchoidal to uneven |
| Mohs scale hardness | 5 (defining mineral) |
| Luster | Vitreous to subresinous |
| Streak | White |
| Diaphaneity | Transparent to translucent |
| Specific gravity | 3.16–3.22 |
From the Wikipedia article
Apatite is a group of phosphate minerals, usually hydroxyapatite, fluorapatite and chlorapatite, with high concentrations of OH−, F− and Cl− ion, respectively, in the crystal. The formula of the admixture of the three most common endmembers is written as Ca10(PO4)6(OH,F,Cl)2, and the crystal unit cell formulae of the individual minerals are written as Ca10(PO4)6(OH)2, Ca10(PO4)6F2 and Ca10(PO4)6Cl2.
Source
Source record: crystal-compendium/apatite/minerals.json. Fetched from English Wikipedia by the operator 2 October 2026.
https://en.wikipedia.org/wiki/Apatite — revision id 1376719845. Text and properties from Wikipedia, licensed CC BY-SA 4.0.