Tenacity
-
Brittle
Solubility
-
-
Durability
-
-
Specific Gravity
3.28-3.315.00-5.30
1
7.18
👆🏻
Fracture
Conchoidal
Uneven, ConchoidalWalter Schumann, Conchoidal
Cleavage
None observed
None, may show partings on {0001} and {10 1 1}
Mohs Hardness
6.5-7.56
2
10
👆🏻
Chemical Composition
Al 6B 5O 15(F,OH) 3Ulrich Henn and Claudio C.
Fe 2O 3Arthur Thomas , Gemstones (2009)