This paper offers useful data in identification of emeralds by using a spectrophotometer which is a very useful method for its quick and non destructive measurement. UV-VIS and NIR spectrum have been obtained on a few hundreds emerald samples of different origins, both natural and synthetic. By the UV-VIS spectrum, a dominant absoption due to Cr can be seen on the natural Colombian emeralds, while the absorption due to Cr and Fe are seen on the natural emeralds other than Colombian samples. On the hydrothermally grown synthetic emeralds, Cr caused absorption can be seen and a high transmission of UV can be recognized. On the Russian synthetic emeralds, a Ni related peak of absorption can be seen. On the flux grown synthetic emeralds, only Cr caused absorption can be seen and transmission peak of UV shifted to the higher wavelength side can be seen as compared to the Colombian samples. By the NIR(1200-2700nm) spectrum, the origin of emeralds and the synthetic conditions can be conjectured from the absorption peaks, since they show the presence and state of H_2O.
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