Tenacity
Brittle
-
Solubility
insoluble in water
-
Durability
-
-
Specific Gravity
5.00-5.203.03-3.18
1
7.18
👆🏻
Fracture
Uneven, Conchoidal, ConchoidalWalter Schumann
Uneven, Irregular, Conchoidal
Cleavage
Indistinct on {001}; partings on {011} and {111}
{???} Indistinct
Mohs Hardness
6-6.57-7.5
2
10
👆🏻
Chemical Composition
FeS 2Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Na(Mg 3)Al 6(Si 6O 18)(BO 3) 3(OH) 3(OH)Gemdat.org , Management Team (2012)