Tenacity
-
Brittle
Solubility
-
insoluble in water
Durability
-
-
Specific Gravity
2.55-2.655.00-5.20
1
7.18
👆🏻
Fracture
Conchoidal
Uneven, Conchoidal, ConchoidalWalter Schumann
Cleavage
Perfect {10 1 0}
Indistinct on {001}; partings on {011} and {111}
Mohs Hardness
5.5-66-6.5
2
10
👆🏻
Chemical Composition
(Na,Ca,K) 8(Si,Al) 12O 24(SO 4,Cl,CO 3) 3(H 2O)Arthur Thomas , Gemstones (2009)
FeS 2Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references