Tenacity
-
Brittle
Solubility
-
-
Durability
-
-
Specific Gravity
2.90-3.103.20-3.32
1
7.18
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Fracture
Splintery, Granular
Uneven, Conchoidal
Cleavage
None
Poor
Mohs Hardness
6-6.56-6.5
2
10
👆🏻
Chemical Composition
Ca 2(Mg,Fe) 5(OH) 2Walter Schumann , Gemstones of the world (2001) More from other references
(Mg,Fe2+ ) 7(SiO 4) 3(F,OH) 2Anthony et al , Handbook of mineralogy (2001)