1 Physical Properties
1.1 Tenacity
1.2 Solubility
Not Available
Not Available
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
1.5 Fracture
Conchoidal, Brittle, Conchoidal
ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009), Conchoidal, Brittle
1.6 Cleavage
Good on (110)
{111} Indistinct, {111} Indistinct, {111} Indistinct
1.7 Mohs Hardness
1.8 Chemical Composition
NaCa2Mg5Si7AlO22(OH)2
(Ca,Na) 2Ta 2O 6(O,OH,F)Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references