previous sign calendar months(Nov 22 – Dec 21) next sign Sapphire fact file Crystal Structure: hexagonal Chemical Composition: Corundum ( Aluminum oxide- Al203 ) Hardness: 9 MOHS Refractive Index: 1.762 to 1.77 Colors: yellow, green, pink, clear, and blue A…
previous sign calendar months(Feb 22 – Mar 21) next sign Sapphire fact file Crystal Structure: hexagonal Chemical Composition: Corundum ( Aluminum oxide- Al203 ) Hardness: 9 MOHS Refractive Index: 1.762 to 1.77 Colors: yellow, green, pink, clear, and blue A…