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
Uneven, Brittle, Metallic
Conchoidal, ConchoidalWalter Schumann, Gemstones of the world (2001), Brittle
1.6 Cleavage
Perfect on [001] imperfect on [100]
Distinct on {11 2 0}, imperfect on {10 1 1}
1.7 Mohs Hardness
1.8 Chemical Composition
(K,Na) 3(Fe2+ ,Mn) 7Ti 2Si 8O 24(O,OH) 7Anthony et al , Handbook of mineralogy (2001)
Be 2SiO 4Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references