Tenacity
Brittle
-
Solubility
-
-
Durability
-
-
Specific Gravity
2.33-2.371.98-2.50
1
7.18
👆🏻
Fracture
ConchoidalWalter Schumann
ConchoidalWalter Schumann
Cleavage
Perfect on {010}, good on {100}
None
Mohs Hardness
7.55.5-6.5
2
10
👆🏻
Chemical Composition
Be 2BO 3(OH)Ulrich Henn and Claudio C.
SiO 2 · nH 2OWalter Schumann , Gemstones of the world (2001)