1 Physical Properties
1.1 Tenacity
1.2 Solubility
Not Available
Not Available
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
3.34-3.443.50-3.60
1
7.18
1.5 Fracture
ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009), Conchoidal, Brittle
Uneven, Brittle, Metallic, Brittle, Metallic, Brittle, Metallic
1.6 Cleavage
{111} Indistinct, {111} Indistinct, {111} Indistinct
Good on {110}, (110) ^ (1 1 0) ≈87°; parting on {100}
1.7 Mohs Hardness
1.8 Chemical Composition
(K,Cs)Al 4Be 4(B,Be) 12O 28Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
(Na,Fe,Ca)Si 2O 6Ulrich Henn and Claudio C.