1 Physical Properties
1.1 Tenacity
Not Available
Not Available
1.2 Solubility
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
2.5 Fracture
Conchoidal, Uneven, ConchoidalArthur Thomas, Gemstones (2009)
Conchoidal, Conchoidal, Gemstones of the world (2001)
2.6 Cleavage
2.7 Mohs Hardness
2.11 Chemical Composition
(Mg,Fe2+ )Al 2O 4Gemdat.org , Management Team (2012) More from other references
SiO 2 · nH 2OWalter Schumann , Gemstones of the world (2001)