Large samples of emeralds from eight deposits in Brazil, China, Zambia, Russia, Afghanistan, Colombia, and Tanzania were studied using pulsed cathodoluminescence to develop a nondestructive method for determining their region of origin. The average wavelength, variance, and inverse effective width of the luminescence band in the 660-870 nm wavelength range of these minerals followed normal distributions with intensities characteristic of each of the regions of origin. Based on this result, a statistical luminescence method for determining the region of origin of the minerals was proposed and tested. This method uniquely determined the region of origin for more than 80 of the emeralds. (C) 2019 Optical Society of America
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