Tenacity
-
Brittle
Solubility
-
-
Durability
-
-
Specific Gravity
3.355-3.4333.90-4.00
1
7.18
👆🏻
Fracture
Uneven
Conchoidal
Cleavage
{???} Good, {???} Good
Perfect on {001}, good on {210}, poor on {010}
Mohs Hardness
-99993-3.5
2
10
👆🏻
Chemical Composition
(Ca,Mn2+ ,Fe2+ ) 3Al 2BSi 4O 15(OH)Anthony et al , Handbook of mineralogy (2001)
SrSO 4Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references