Specific Gravity: 4,00
Crystal System: trigonal
Index of Refraction : 1,758-1,765
Transparency: from transparent to opaque
Ruby is composed of aluminum, chromium, and iron. Color ranges are in a variety of shades of red Burma is the source of the finest variety. Other mines are located in Thailand, Sri Lanka, Madagascar and Tanzania .
One of the main characheristics of Corundum is the optical effect called asterism, a star effect due to rutile needle inclusions arranged in a star pattern