Tenacity
-
-
Solubility
-
-
Durability
-
-
Specific Gravity
2.50-2.803.65-4.55
1
7.18
👆🏻
Fracture
-
Conchoidal
Cleavage
Perfect
None, but may exhibit slight parting
Mohs Hardness
5-6.57.5-8
2
10
👆🏻
Chemical Composition
Na 4(Al,Si) 12O 24Cl to Ca 4(Si,Al) 12O 24(CO 3,SO 4)Arthur Thomas , Gemstones (2009)
(Mg,Zn)Al 2O 4Gemdat.org , Management Team (2012)