1 Physical Properties
1.1 Tenacity
1.2 Solubility
Not Available
Not Available
1.5 Durability
1.7 Specific Gravity
1.8 Fracture
Uneven, Conchoidal, UnevenWalter Schumann, Gemstones of the world (2001)
Conchoidal, ConchoidalArthur Thomas, Gemstones (2009), Brittle
1.9 Cleavage
Perfect {010}, imperfect {100}
On {10 1 0}, perfect; parting on {000 1 }
1.10 Mohs Hardness
1.11 Chemical Composition
Ca2Al3(SiO4)3(OH)
(Zn,Mn2+ )OMichael OâDonoghue , Gems, Sixth Edition (2006)