Allochromatic gems are gems which might be colored by impurities. If they have been fully pure, they would be colorless. The colour of all allochromatic gems is produced by defects. As a result, all color in corundum is because of defects. Exactly what are you looking ahead to? Go ahead https://trackbookmark.com/story19487225/not-known-facts-about-sri-lankan-pukhraj