Physical Properties
Tenacity
Brittle
Not Available
Solubility
Soluble
Not Available
Durability
Not Available
Not Available
Specific Gravity
2.75
3.77-3.95
Fracture
Uneven, UnevenArthur Thomas, Gemstones (2009), Conchoidal, Brittle
Not Available
Cleavage
Imperfect on {110}
Not Available
Mohs Hardness
5.5
6.5
Chemical Composition
(Na,Ca) 8Al 6Si 6O 24(SO 4,S,Cl) 2Ulrich Henn and Claudio C.
Ca 3Fe 2(SiO 4) 3Ulrich Henn and Claudio C.
