This study of yellow sapphires was determined by the lack of clarity while in the literature as for the origin of your yellow coloration. On reflection, this uncertainty was the results of 3 factors. Initially, the Fe3+ focus in natural stones spans A variety of approximately four–4750 ppma, but only https://www.tumblr.com/thegemjournal/759696203354128384/understanding-the-unique-characteristics-of-yellow?source=share