Tenacity
-
Brittle
Solubility
-
-
Durability
-
-
Specific Gravity
3.25-3.452.60-2.65
1
7.18
👆🏻
Fracture
Conchoidal, Uneven
Uneven, Conchoidal
Cleavage
Good on {110}
Perfect on {001}, very good on {010}, imperfect on {110}
Mohs Hardness
6.56-6.5
2
10
👆🏻
Chemical Composition
Mg 3Al 6(Si,Al,B) 5O 21(OH)Walter Schumann , Gemstones of the world (2001) More from other references
NaAlSi 3O 8Michael OâDonoghue , Gems, Sixth Edition (2006)