Tenacity
Brittle
-
Solubility
-
-
Durability
-
-
Specific Gravity
2.33-2.373.76-3.77
1
7.18
👆🏻
Fracture
ConchoidalWalter Schumann
-
Cleavage
Perfect on {010}, good on {100}
{110} Perfect, {110} Perfect
Mohs Hardness
7.55-6
2
10
👆🏻
Chemical Composition
Be 2BO 3(OH)Ulrich Henn and Claudio C.
(Fe,Mn) 7Si 7O 21Ulrich Henn and Claudio C.