Allochromatic gems are gems that are coloured by impurities. If they had been completely pure, they would be colorless. The color of all allochromatic gems is produced by defects. Hence, all shade in corundum is attributable to defects. Delhi is the primary place for gem lovers, and it is one https://bookmarksea.com/story18086952/natural-pukhraj-from-sri-lanka-things-to-know-before-you-buy