Tenacity
Solubility
Durability
Specific Gravity
Fracture
Cleavage
Mohs Hardness
Chemical Composition
(Mg,Fe) 5(SiO 4) 2(F,OH) 2Ulrich Henn and Claudio C.
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