1 Physical Properties
1.1 Tenacity
1.2 Solubility
Gelatinises in acids
Not Available
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
1.13 Fracture
Uneven, Conchoidal, Brittle
Gems, Sixth Edition (2006)
1.14 Cleavage
1.15 Mohs Hardness
1.16 Chemical Composition
(Na,Ca)4-8Al6Si6(O,S)24(SO4,Cl)1-2
SiO2 (with a high level of nickel impurities )