Mineral

a and b

c

c/a

Mesh

Emperical formula

Fluoroap atite

9.371

6.885

0.734

523.12

Ca₅(PO₄)₃F

Hydroxylapatite

9.352

6.882

0.735

521.26

Ca₅(PO₄)₃(OH)

Francolite

9.340

6.880

0.736

519.77

CaF(Ca,C)₄[(P,C) (O,OH,F)₄]

Dahllite

9.450

6.885

0.725

532.09

(Ca_9.35Na_1.07)(PO₄)_5.46(CO₃)_1.36O₂