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
2.62-2.67Not Available
1
7.18
1.5 Fracture
Gems, Sixth Edition (2006), Gems, Sixth Edition (2006), Uneven
ConchoidalArthur Thomas, Gemstones (2009)
1.6 Cleavage
From the Greek, oligos and kasein, little cleavage.
Not Available
1.7 Mohs Hardness
1.8 Chemical Composition
Na(90-70%)Ca(10-30%)(Al,Si)AlSi 2O 8Michael OâDonoghue , Gems, Sixth Edition (2006)
MnTa 2O 6Walter Schumann , Gemstones of the world (2001) More from other references