Tenacity
Brittle
Brittle
Solubility
-
-
Durability
-
-
Specific Gravity
3.20-3.325.00-5.30
1
7.18
👆🏻
Fracture
Uneven, Conchoidal
Uneven, ConchoidalWalter Schumann, Conchoidal
Cleavage
Poor
None, may show partings on {0001} and {10 1 1}
Mohs Hardness
6-6.56
2
10
👆🏻
Chemical Composition
(Mg,Fe2+ ) 7(SiO 4) 3(F,OH) 2Anthony et al , Handbook of mineralogy (2001)
Fe 2O 3Arthur Thomas , Gemstones (2009)