1 Physical Properties
1.1 Tenacity
1.2 Solubility
Partly soluble in HCl.
Gelatinises in acids
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
1.5 Fracture
ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)
Uneven, Conchoidal, Brittle
1.6 Cleavage
{100} perfect; {110} and {1 1 0} good; {010} poor
Distinct on {110}
1.7 Mohs Hardness
1.8 Chemical Composition
(Ca,Mn2+ )Si 3O 9Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
(Na,Ca)4-8Al6Si6(O,S)24(SO4,Cl)1-2