1 Physical Properties
1.1 Tenacity
1.2 Solubility
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
1.5 Fracture
Uneven, UnevenArthur Thomas, Gemstones (2009), Conchoidal, Brittle
Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001), Brittle, Conchoidal
1.6 Cleavage
Imperfect on {110}
{110} Perfect, {010} Indistinct
1.7 Mohs Hardness
1.8 Chemical Composition
(Na,Ca) 8Al 6Si 6O 24(SO 4,S,Cl) 2Ulrich Henn and Claudio C.
(Ca,Na)(Mg,Fe,Al,Ti)(Si,Al) 2O 6Anthony et al , Handbook of mineralogy (2001)