Specific Gravity: 4,00
Crystal System: trigonal
Index of Refraction: 1,758-1,765
Transparency: from transparent to opaque
Sapphire is composed of silicate, iron, and titanium.
It occurs in a variety of shades of blue.
Sapphire mines are located in Burma, Sri Lanka, Thailand, Kashmir, Australia, and Madagascar .Like Ruby, Sapphire is characterized by the optical effects of asterism and chatoyancy.