This examine of yellow sapphires was enthusiastic by the lack of clarity within the literature as to your origin from the yellow coloration. In retrospect, this uncertainty was the result of a few aspects. Initially, the Fe3+ focus in natural stones spans a range of somewhere around four–4750 ppma, but https://www.tumblr.com/thegemjournal/759696203354128384/understanding-the-unique-characteristics-of-yellow?source=share