Study on Spectral Characteristics and Differences of Natural and Pink Dushan Jade
lo reveal the difference in material composition,color origin,and scientific identification characteristics of natural pink Dushan jade and dyed pink Dushan jade from Nanyang,Henan Province,conventional gemological characteristics,infrared spectrum,Raman spectrum,UV-visible absorption spectrum,electron paramagnetic resonance spectrum,and photoluminescence spectrum were tested.The results show that the refractive index and relative density of Dushan jade are concentrated,which is close to that of plagioclase.The natural red-only jade shows two refractive index values of plagioclase and zoisite in different positions.Infrared spectra combined with Raman spectra show that the pink part of the natural red monozoite is consistent with the characteristic spectrum peak of zoisite,indicating that the zoisite has a high degree of fossilization.In contrast,the white and green parts are dominated by basic plagioclase.The chromaticity of Dushan jade has a low degree of zoisite mineralization,so the conventional gemological parameters are close to that of plagioclase,which often requires dyeing treatment and shows abnormal yellow-white long-wave ultraviolet fluorescence.The UV spectrum of the natural samples showed a wide and slow absorption band near 522 nm,which revealed that Mn was the main cause of the natural red-jade pink color.The electron paramagnetic spectrum further reveals the six-fold hyperfine structure of Mn2+,which is the 6A1 → 4T1(4G)spin-forbidden transition of Mn2+in the octahedral field.The staining of Dushan jade shows the dye absorption near 549 nm,corresponding to the intense luminescence center at 578～589 nm in the photoluminescence spectrum.UV fluorescent lamp,UV-VIS spectrum,and photoluminescence spectrum can be effective nondestructive testing methods for natural red and colored pink Dushan jade.
万方数据
维普
