
Specimen of the weekMineral · Phosphates
Apatite
Apatite is not just one neat mineral with one fixed composition. In everyday mineral collecting and geology, “apatite” is often used for a group of related calcium phosphate minerals.
- Mohs hardness
- 5. Apatite is the reference mineral for hardness 5 on the Mohs scale.
- Common simplified formula
- Ca5(PO4)3(F, Cl, OH). The main end-members are fluorapatite, hydroxylapatite, and…
- Crystal system
- Hexagonal for the common apatite-group minerals.

















