1 Physical Properties
1.1 Tenacity
1.2 Solubility
Not Available
Not Available
1.3 Durability
1.4 Specific Gravity
1.5 Fracture
Uneven, Conchoidal, UnevenWalter Schumann, Gemstones of the world (2001)
Conchoidal, Brittle
1.6 Cleavage
Perfect {010}, imperfect {100}
{001} perfect; {111} imperfect, may exhibit parting on , {011}
1.7 Mohs Hardness
1.8 Chemical Composition
Ca2Al3(SiO4)3(OH)
MgOMichael OâDonoghue , Gems, Sixth Edition (2006)