Tenacity
Brittle
-
Solubility
-
-
Durability
-
-
Specific Gravity
1.793.95-4.10
1
7.18
👆🏻
Fracture
Irregular/uneven
Uneven
Cleavage
Perfect on {10bar10}
{110} Perfect, {110} Perfect, {110} Perfect
Mohs Hardness
2.53.5-4
2
10
👆🏻
Chemical Composition
Ca6(Al,Si)2(SO4)2B(OH)4(OH,O)12•26(H2O)
(Zn,Fe)SMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references