1 Physical Properties
1.1 Tenacity
Not Available
Not Available
1.2 Solubility
Not Available
Not Available
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
1.5 Fracture
Uneven, Subconchoidal, Uneven, Subconchoidal, Splintery, UnevenArthur Thomas, Gemstones (2009)
Handbook of mineralogy (2001)
1.6 Cleavage
Good on {110}, poor on {100}
None
1.7 Mohs Hardness
1.8 Chemical Composition
Al 2SiO 5Michael OâDonoghue , Gems, Sixth edition (2006) More from other references
Na x[Fe2+2(Al,Fe3+ )]Al 6(BO 3) 3Si 6O 18(OH) 4Anthony et al , Handbook of mineralogy (2001)