1 Physical Properties
1.1 Tenacity
1.2 Solubility
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
1.5 Fracture
ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009), Conchoidal, Brittle
Uneven, Uneven, Gems, Difficult, Fibrous
1.6 Cleavage
{111} Indistinct, {111} Indistinct, {111} Indistinct
None – parting in 3 directions
1.7 Mohs Hardness
1.8 Chemical Composition
(Ca,Na) 2Ta 2O 6(O,OH,F)Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Al 2O 3Arthur Thomas , Gemstones (2009)