This analyze of yellow sapphires was inspired by The shortage of clarity while in the literature as into the origin from the yellow coloration. Looking back, this uncertainty was the result of a few things. First, the Fe3+ concentration in natural stones spans a range of approximately four–4750 ppma, but https://www.tumblr.com/thegemjournal/759696203354128384/understanding-the-unique-characteristics-of-yellow?source=share