Allochromatic gems are gems that are coloured by impurities. Whenever they had been totally pure, they might be colorless. The color of all allochromatic gems is produced by defects. Therefore, all coloration in corundum is because of defects. Healing Advantages: The stone also offers quite a few healing Positive aspects https://www.tumblr.com/thegemjournal/759696203354128384/understanding-the-unique-characteristics-of-yellow?source=share