Tenacity
-
Brittle
Solubility
-
-
Durability
-
-
Specific Gravity
3.1-3.53.87-4.14
1
7.18
👆🏻
Fracture
Granular
Subconchoidal, Conchoidal
Cleavage
None
Poor on {120}, in traces on {001}
Mohs Hardness
5-65.5-6
2
10
👆🏻
Chemical Composition
Ca 2(Mg,Fe)Al 2(SiO 4)(Si 2O 7)(OH) 2 · H 2O)Arthur Thomas , Gemstones (2009)
TiO 2Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references