Tenacity
Solubility
Durability
Specific Gravity
Fracture
Cleavage
Mohs Hardness
Chemical Composition
Conchoidal, Uneven, Conchoidal to uneven
[0001] indistinct, [1010] indistinct
Ca 5(PO 4) 3(F,OH,Cl)Walter Schumann , Gemstones of the world (2001) More from other references
Good on [110] and on [001]
[ ]Na2(Mg3Al2)Si8O22(OH)2