Tenacity
Solubility
Durability
Specific Gravity
Fracture
Cleavage
Mohs Hardness
Chemical Composition
{010} perfect, {110} distinct, {100} in traces
AlO(OH)Walter Schumann , Gemstones of the world (2001) More from other references
{111} Indistinct, {111} Indistinct, {111} Indistinct
(Ca,Na) 2Ta 2O 6(O,OH,F)Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references