Tenacity
Brittle
Brittle
Solubility
Soluble
Soluble
Durability
-
-
Specific Gravity
2.95-2.963.25-3.35
1
7.18
👆🏻
Fracture
Conchoidal
Conchoidal, ConchoidalWalter Schumann
Cleavage
None
Perfect in three directions
Mohs Hardness
7-7.55
2
10
👆🏻
Chemical Composition
Mg 3B 7O 13ClMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references
CuSiO 2(OH) 2Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references