Tenacity
Brittle
Brittle
Solubility
-
-
Durability
-
-
Specific Gravity
2.33-2.373.19-3.23
1
7.18
👆🏻
Fracture
ConchoidalWalter Schumann
Conchoidal
Cleavage
Perfect on {010}, good on {100}
{110} good
Mohs Hardness
7.55-6
2
10
👆🏻
Chemical Composition
Be 2BO 3(OH)Ulrich Henn and Claudio C.
KNa 2Li(Fe2+ ,Mn2+ ) 2Ti 2Si 8O 24Michael OâDonoghue , Gems, Sixth Edition (2006)