Gemmological Characteristics of GE Synthetic Jadeite Jade

By using Fourier transform infrared spectroscopy,laser Raman spectroscopy,electron microprobe and cathodoluminescence microscope,the chemical compositions,vibrational spectrum,absorption spectrum and cathodoluminescence of the latest developed synthetic jadeite jade synthesized by American General Electric Corporation(GE) are investigated.The results show that GE synthetic jadeite jade consists primarily of w(SiO₂)=59.74%~61.72%,w(Al₂O₃)=23.90%~24.97%,w(Na₂O)=13.65%~(14.85)% and secondarily of w(Cr₂O₃)=0.05%~0.07%,w(K₂O)=0.02%~0.04%,w(CaO)=0.02%~0.06%.The IR absorption bands of 3 373,3 471 and 3 614 cm^-1 are resulted from the hydroxyl stretching vibration in GE synthetic jadeite jade.A group of sharp laser Raman spectral peaks of 376,700,989,1 039 cm^-1 indicate that GE synthetic jadeite jade has silicon-oxygen tetrahedron chain structure and crystal perfection.The colouration of GE synthetic jadeite jade is attributed mainly to the absorption at 445 and 630 nm,which is resulted from the transition of ⁴A₂→ ⁴T₂and ⁴A₂→ ⁴T₁in Cr³⁺.