Spinel is an oxide mineral with a chemical composition Mg Al ₂ O₄ in the cubic crystal system. It is very hard and hardness is 7.5 to 8.0 on Mohs hardness scale. Spinel is often found in octahedral crystals and has a crystal system isometric.
Spinel is a gemstone mineral that has been confused with Ruby and Sapphires over 1000 years. Spinel occurs in the same bright red and blue colors as Rubies and Sapphires. Spinel occurs in a wide variety of colors bright red and deep blue is aspectual specimens and other colors are black, pink, green, purple, white and brown.
Spinel is very resistant to chemical and physical weathering. Spinel is also a broad group of minerals include gahnite, magnetite, franklinite, chromites, chrysoberyl and columbite-Tantalite.
Most Spinel of Ruby –red color are mined from Sri Lanka is very special and, Cambodia, Vietnam, Myanmar and other countries also where Spinels are mined include Afghanistan, Nepal and Madagascar. Spinel is new birthstone for August