Spinel Is a Magnesium Aluminum Oxide with formula MgAl2O4 and hardness of 8. A stone well know since thousands year often confuse with ruby in the past, is becoming scarce and difficult to get in 3-4 carat size with good red color. This is an investment stone. Location: Burma Size:8.4x5.9x4.6 mm. Weight:1.76 ct. CODE#2902