Tenacity
-
Brittle
Solubility
-
insoluble in water
Durability
-
-
Specific Gravity
3.0-3.55.00-5.20
1
7.18
👆🏻
Fracture
Uneven
Uneven, Conchoidal, ConchoidalWalter Schumann
Cleavage
Perfect
Indistinct on {001}; partings on {011} and {111}
Mohs Hardness
5-66-6.5
2
10
👆🏻
Chemical Composition
Na(CaNa)(Mg,Fe++)5(Si8O22)(OH)2
FeS 2Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references