Tenacity
-
Brittle
Solubility
-
-
Durability
-
-
Specific Gravity
3.85-3.943.7-3.8
1
7.18
👆🏻
Fracture
Conchoidal, Uneven
Subconchoidal, Conchoidal
Cleavage
{010} Good, {100} Distinct
Distinct on {010}
Mohs Hardness
5-5.57-7.5
2
10
👆🏻
Chemical Composition
(Mn2+ ,Fe2+ ,Mg,Ca) 2(PO 4)(F,OH)Michael OâDonoghue , Gems, Sixth Edition (2006)
(Fe,Mg,Zn) 2Al 9(Si,Al) 4O 22(OH) 2Ulrich Henn and Claudio C.