Tenacity
-
-
Solubility
-
-
Durability
-
-
Specific Gravity
3.43-3.442.50-2.80
1
7.18
👆🏻
Fracture
-
-
Cleavage
None Observed
Perfect
Mohs Hardness
6.5-75-6.5
2
10
👆🏻
Chemical Composition
Ca 2(Mg,Al) 6(Si,Al,B) 6O 20Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Na 4(Al,Si) 12O 24Cl to Ca 4(Si,Al) 12O 24(CO 3,SO 4)Arthur Thomas , Gemstones (2009)