This analyze of yellow sapphires was inspired by The dearth of clarity in the literature as to your origin on the yellow coloration. In retrospect, this uncertainty was the results of 3 aspects. First, the Fe3+ focus in natural stones spans An array of somewhere around 4–4750 ppma, but only https://www.tumblr.com/thegemjournal/759696203354128384/understanding-the-unique-characteristics-of-yellow?source=share