Tenacity
-
-
Solubility
-
-
Durability
-
-
Specific Gravity
2.62-2.674.76-5.03
1
7.18
👆🏻
Fracture
Uneven
Conchoidal
Cleavage
From the Greek, oligos and kasein, little cleavage.
None
Mohs Hardness
6-6.55.5-6.5
2
10
👆🏻
Chemical Composition
Na(90-70%)Ca(10-30%)(Al,Si)AlSi 2O 8Michael OâDonoghue , Gems, Sixth Edition (2006)
(Mn2+ ,Fe2+ ,Mg)(Fe3+ ,Mn3+ ) 2O 4Anthony et al , Handbook of mineralogy (2001)