1 Physical Properties
1.1 Tenacity
1.2 Solubility
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
1.5 Fracture
Uneven, Uneven, Gems, Sixth Edition (2006), Uneven, Conchoidal
Conchoidal, Uneven, ConchoidalArthur Thomas, Gemstones (2009)
1.6 Cleavage
Perfect on {001}, very good on {010}, imperfect on {110}
Indistinct
1.7 Mohs Hardness
1.8 Chemical Composition
NaAlSi 3O 8Michael OâDonoghue , Gems, Sixth Edition (2006)
(Mg,Fe2+ )Al 2O 4Gemdat.org , Management Team (2012) More from other references