Abstract:
Emerald often appears with fissures and people have been trying to cover and hide the fissures by oiling and fillings,as well as reducing the risks of processing.As the increasing and wide use of fillings for emerald clarity enhancement,people started to research a better filling material.In this paper,six emerald samples were chosen to be filled by ExCel,which is currently acknowledged as the best filling in global emerald trade.Magnification,infrared spectroscopy analysis,fluorescence characteristics and other identification tests were carried out and these samples were analyzed before and after filling process by ExCel.The contrast experiment aims to gain a deeper understanding about the filling method of emeralds and the laboratory identification characteristics of emeralds filled by ExCel.During this study,the infrared spectra show characteristic peaks of epoxy resin at 3 000-3 100cm
-1,and a broad absorption peak at 2 930cm
-1.Along with the special fluorescence characteristics,the infrared spectrum could be the main identification evidence for emeralds filled by ExCel.