All but the iodoapatite have been prepared. The
barium halophosphates or barium apatites comprise
the compound, Ba5X(PO4)3 where X is OH, F, Cl Br or I.
All can be formed (with the exception of the hydroxyapatite
which must be formed in solution) by solid-state
reaction:
6BaHPO4 + 3BaCO3 + BaX2 + heat?Ba10X2(PO4)6
+ 3CO2 + 3H2O
