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
Conchoidal, ConchoidalArthur Thomas, Gemstones (2009), Brittle
1.6 Cleavage
Imperfect on {110}
On {10 1 0}, perfect; parting on {000 1 }
1.7 Mohs Hardness
1.8 Chemical Composition
(Na,Ca) 8Al 6Si 6O 24(SO 4,S,Cl) 2Ulrich Henn and Claudio C.
(Zn,Mn2+ )OMichael OâDonoghue , Gems, Sixth Edition (2006)