Detection of Emerald from Xinjiang by Electron Probe Microanalyzer and X-ray Diffractometer

The high grade emeralds (beryls) which were first discovered in Xinjiang have attracted attention of domestic and foreign scholars. In this paper, electron probe microanalyzer (EPMA) and X-ray diffractometer (XRD) were used for obtaining the data of chemical components, crystal cell parameters and diffraction patterns of the emeralds. The analytical results showed that the content of Cr₂O₃ in emeralds was higher up to 0.21% to 0.54% and the emerald cell parameters were a₀=0.9233 nm, c₀=0.9206 nm, Z=2 with main powder diffraction spectral lines of 2.871 (100), 3.257 (100), 7.996 (100).