Tenacity
-
Brittle
Solubility
-
insoluble
Durability
-
-
Specific Gravity
3.1-3.56.86-7.03
1
7.18
👆🏻
Fracture
Granular
Subconchoidal, Uneven, Conchoidal, Irregular
Cleavage
None
{100} imperfect, {110} indistinct; partings on {111} or {011}
Mohs Hardness
5-66-7
2
10
👆🏻
Chemical Composition
Ca 2(Mg,Fe)Al 2(SiO 4)(Si 2O 7)(OH) 2 · H 2O)Arthur Thomas , Gemstones (2009)
SnO 2Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references