Tenacity
Brittle
-
Solubility
-
-
Durability
-
-
Specific Gravity
3.20-3.323.05-3.08
1
7.18
👆🏻
Fracture
Uneven, Conchoidal
Subconchoidal, Uneven, Conchoidal
Cleavage
Poor
Poor on {100}
Mohs Hardness
6-6.55
2
10
👆🏻
Chemical Composition
(Mg,Fe2+ ) 7(SiO 4) 3(F,OH) 2Anthony et al , Handbook of mineralogy (2001)
Mn2+ Al(PO 4)(OH) 2H 2OMichael OâDonoghue , Gems, Sixth Edition (2006)