This research of yellow sapphires was determined by the lack of clarity within the literature as to the origin with the yellow coloration. In retrospect, this uncertainty was the result of 3 factors. 1st, the Fe3+ concentration in natural stones spans A selection of about four–4750 ppma, but only concentrations https://bookmark-vip.com/story18134913/indicators-on-sri-lankan-yellow-sapphire-you-should-know