1 Physical Properties
1.1 Tenacity
1.2 Solubility
Not Available
Gelatinises in acids
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
1.5 Fracture
Uneven, Subconchoidal, Uneven, Subconchoidal, Splintery, UnevenArthur Thomas, Gemstones (2009)
Uneven, Conchoidal, Brittle
1.6 Cleavage
Good on {110}, poor on {100}
Distinct on {110}
1.7 Mohs Hardness
1.8 Chemical Composition
Al 2SiO 5Michael OâDonoghue , Gems, Sixth edition (2006) More from other references
(Na,Ca)4-8Al6Si6(O,S)24(SO4,Cl)1-2