Tenacity
Brittle
-
Solubility
-
-
Durability
-
-
Specific Gravity
2.60-2.653.26-3.36
1
7.18
👆🏻
Fracture
Uneven, Conchoidal
Conchoidal
Cleavage
Perfect on {001}, very good on {010}, imperfect on {110}
Good on {100}
Mohs Hardness
6-6.56.5-7
2
10
👆🏻
Chemical Composition
NaAlSi 3O 8Michael OâDonoghue , Gems, Sixth Edition (2006)
(Ca,Fe,Mn,Mg) 3Al 2BSi 4O 15(OH)Walter Schumann , Gemstones of the world (2001) More from other references