1 Physical Properties
1.1 Tenacity
1.2 Solubility
Not Available
Not Available
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
3.355-3.4335.50-5.90
1
7.18
1.5 Fracture
Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001)
Conchoidal, ConchoidalArthur Thomas, Gemstones (2009), Brittle
1.6 Cleavage
{???} Good, {???} Good
On {10 1 0}, perfect; parting on {000 1 }
1.7 Mohs Hardness
1.8 Chemical Composition
(Ca,Mn2+ ,Fe2+ ) 3Al 2BSi 4O 15(OH)Anthony et al , Handbook of mineralogy (2001)
(Zn,Mn2+ )OMichael OâDonoghue , Gems, Sixth Edition (2006)