It is Magnesium Aluminum Oxide having the chemical formula MgAl2O4.
Red, blue, green, orange, mauve, violet, yellow, purple, brown and black.
White or grayish white.
1.71 - 1.76 (approx)
Transparent to translucent and sometimes nearly opaque.
Isometric â€“ Cubic Hexagonal crystal system.
Uneven to conchoidal.
Synthetic stones are available.
Myanmar (Burma), Afghanistan, Madagascar, Pakistan, Australia, Italy, Sri Lanka (Ceylon), Brazil, Tanzania, Sweden, Turkey, Russia and United States.
Only general gemstone precautions required.