1 Physical Properties
1.1 Tenacity
Not Available
Not Available
1.2 Solubility
Not Available
Not Available
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
3.34-3.443.76-3.77
1
7.18
1.5 Fracture
ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009), Conchoidal, Brittle
UnevenArthur Thomas, Gemstones (2009), UnevenArthur Thomas, Gemstones (2009)
1.6 Cleavage
{111} Indistinct, {111} Indistinct, {111} Indistinct
{110} Perfect, {110} Perfect
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
(Fe,Mn) 7Si 7O 21Ulrich Henn and Claudio C.