Tenacity
Brittle
-
Solubility
-
-
Durability
-
-
Specific Gravity
2.97-3.033.03-3.18
1
7.18
👆🏻
Fracture
Uneven, ConchoidalWalter Schumann, Conchoidal
Uneven, Irregular, Conchoidal
Cleavage
{001} Poor
{???} Indistinct
Mohs Hardness
77-7.5
2
10
👆🏻
Chemical Composition
CaB 2(SiO 4) 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)