1 Physical Properties
1.1 Tenacity
1.2 Solubility
Not Available
Not Available
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
2.62-2.673.21-3.38
1
7.18
1.5 Fracture
Gems, Sixth Edition (2006), Gems, Sixth Edition (2006), Uneven
Irregular/uneven, Uneven
1.6 Cleavage
From the Greek, oligos and kasein, little cleavage.
Perfect on {001}
1.7 Mohs Hardness
1.8 Chemical Composition
Na(90-70%)Ca(10-30%)(Al,Si)AlSi 2O 8Michael OâDonoghue , Gems, Sixth Edition (2006)
Ca 2Al 3(SiO 4) 3(OH)Walter Schumann , Gemstones of the world (2001) More from other references