1 Physical Properties
1.1 Tenacity
Not Available
Not Available
1.2 Solubility
Not Available
Not Available
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
2.58-2.642.62-2.67
1
7.18
1.5 Fracture
Not Available
Gems, Sixth Edition (2006), Gems, Sixth Edition (2006), Uneven
1.6 Cleavage
Not Available
From the Greek, oligos and kasein, little cleavage.
1.7 Mohs Hardness
1.8 Chemical Composition
SiO 2Walter Schumann , Gemstones of the world (2001)
Na(90-70%)Ca(10-30%)(Al,Si)AlSi 2O 8Michael OâDonoghue , Gems, Sixth Edition (2006)