Tenacity
Brittle
Brittle
Solubility
-
-
Durability
-
-
Specific Gravity
3.69-3.813.50-3.60
1
7.18
👆🏻
Fracture
Uneven, Conchoidal to uneven, ConchoidalWalter Schumann
Uneven
Cleavage
Distinct on {110}, imperfect on {010}, poor on {001}
Good on {110}, (110) ^ (1 1 0) ≈87°; parting on {100}
Mohs Hardness
8.56
2
10
👆🏻
Chemical Composition
BeAl 2 O 4
(Na,Fe,Ca)Si 2O 6Ulrich Henn and Claudio C.