Natural corundum is a crystalline form of aluminum oxide (Al2O3) and is one of the hardest minerals known, second only to diamond. It is most commonly recognized in its transparent form as gemstones like sapphires and rubies, which are prized for their beauty and durability. Here are some key points about natural Blue Sapphire
Dimensions for Both: ( 5.72 x 4.56 x 3.07 mm) (6.22 x 4.60 x 3.01 mm )
