Tenacity
-
-
Solubility
-
-
Durability
-
-
Specific Gravity
2.55-2.653.26
1
7.18
👆🏻
Fracture
Conchoidal
Uneven
Cleavage
Perfect {10 1 0}
None
Mohs Hardness
5.5-6-9999
2
10
👆🏻
Chemical Composition
(Na,Ca,K) 8(Si,Al) 12O 24(SO 4,Cl,CO 3) 3(H 2O)Arthur Thomas , Gemstones (2009)
NaFe3+3Fe3+6(BO 3) 3Si 6O 18(O,OH) 4Anthony et al , Handbook of Mineralogy (2001)