Tenacity
Solubility
Durability
Specific Gravity
Fracture
Cleavage
Mohs Hardness
Chemical Composition
{111} Indistinct, {111} Indistinct, {111} Indistinct
(K,Cs)Al 4Be 4(B,Be) 12O 28Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Perfect on {010} imperfect on {100}
Mg 2SiO 4Michael OâDonoghue , Gems, Sixth Edition (2006)