1 Physical Properties
1.1 Tenacity
1.2 Solubility
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
1.5 Fracture
Gemstones (2009)
Uneven, UnevenArthur Thomas, Gemstones (2009), Conchoidal, Brittle
1.6 Cleavage
Not Available
Imperfect on {110}
1.7 Mohs Hardness
1.13 Chemical Composition
Al 2SiO 5Arthur Thomas , Gemstones (2009) More from other references
(Na,Ca) 8Al 6Si 6O 24(SO 4,S,Cl) 2Ulrich Henn and Claudio C.