This analyze of yellow sapphires was motivated by the lack of clarity while in the literature as into the origin of your yellow coloration. On reflection, this uncertainty was the result of 3 components. Initially, the Fe3+ concentration in natural stones spans a range of approximately 4–4750 ppma, but only https://www.tumblr.com/thegemjournal/759696203354128384/understanding-the-unique-characteristics-of-yellow?source=share