Tenacity
Solubility
Durability
Specific Gravity
Fracture
Cleavage
Mohs Hardness
Chemical Composition
{???} Imperfect, {???} Imperfect
Subconchoidal, Conchoidal
Perfect on [001] and [011]
TiO 2Michael OâDonoghue , Gems, Sixth edition (2006) More from other references