光谱学与光谱分析, 2014, 34 (8): 2017, 网络出版: 2014-08-18
青海青玉的振动光谱特征
Vibrational Spectra of Caesious Nephritefrom Qinghai Province
青玉 激光拉曼光谱 红外吸收光谱 颜色成因 青海 Caesious nephrite Raman spectra Infrared absorption spectroscopy Color origin Qinghai
摘要
采用常规宝石学测试方法, 并结合电子探针、红外光谱仪、激光拉曼光谱仪对产自青海格尔木市小灶火河矿点的青玉进行了化学成分和光谱特征研究。测试结果表明, 青海青玉的宝石学物理性质与其他产地软玉相似。电子探针测试显示青海青玉的主要化学成分为MgO、 CaO和SiO2, MgO含量在18.572%~23.603%, CaO含量为12.333%~12.807%, SiO2含量在56.799%~59.926%, 且含量较稳定, 此外还含有较高含量的FeOT(Wt%: 1.924%~8.699%)和一定量的Al2O3, TiO2和Na2O。红外光谱和激光拉曼光谱分析显示, 青海青玉具有透闪石的光谱特征, 其主要组成矿物为透闪石。由于青玉中Mg-Fe2+的类质同象替代及Fe2+含量的不同, 使其红外吸收谱带频率稍有差异。综合化学成分及振动光谱特征分析, 青海青玉的深灰青色主要与其含有高含量的FeOT所致, 其主要致色元素为Fe。
Abstract
Qinghai caesious nephrite is discovered in the 1990s in the Golmud area of Qinghai Province. The conventional gemological testing methods, electron microprobe, infrared absorption spectroscopy and Raman spectroscopy were used in this study to analyze the chemical composition and infrared spectra characteristics of the caesious nephrite, selected from the jade mine of Xiaozhaohuo river in Golmud area. The results show that, the gemological physical properties of the Qinghai caesious nephrite are similar to other origin nephrite. Electron microprobe analysis indicates that the MgO, CaO and SiO2 are the major and stable composition for the caesious nephrite. The content of MgO and CaO are 18.572%~23.603% and 12.333%~12.807% respectively. Moreover, the content of SiO2 is 56.799%~59.926%. In addition, it also contains a higher content of FeOT (Wt%: 1.924%~8.699%) and an amount of Al2O3, TiO2 and Na2O. Infrared absorption and Raman spectra show that the Qinghai caesious nephrite has a characteristic spectral features of tremolite indicating it is mainly composed of tremolite. The different frequency of the infrared absorption bands is due to the difference of Mg—Fe2+ isomorphous substitution and Fe2+ content of the caesious nephrite. Comprehensive analysis of chemical composition and vibrational spectroscopy indicate that the color of dark gray blue for the Qinghai nephrite is mainly related to its high content of FeOT, and the Fe is a main coloring element.
陈全莉, 徐亚兰, 艾苏洁, 贺安琪, 尹作为. 青海青玉的振动光谱特征[J]. 光谱学与光谱分析, 2014, 34(8): 2017. CHEN Quan-li, XU Ya-lan, AI Su-jie, HE An-qi, YIN Zuo-wei. Vibrational Spectra of Caesious Nephritefrom Qinghai Province[J]. Spectroscopy and Spectral Analysis, 2014, 34(8): 2017.