Allochromatic gems are gems which have been colored by impurities. If they ended up entirely pure, they might be colorless. The color of all allochromatic gems is made by defects. Hence, all colour in corundum is a result of defects. Following lights an incense adhere in front of the gemstone https://socialwoot.com/story19651317/a-simple-key-for-natural-yellow-sapphire-from-sri-lanka-unveiled