显微激光拉曼成像技术在淡水无核珍珠研究中的应用

近年来，珍珠中的六方球文石成为珍珠研究的一个热点。利用文石与六方球文石的特征拉曼光谱差异，对淡水无核珍珠样品的两种物象组成进行了测试研究。采用显微激光拉曼成像技术初步确定了淡水无核珍珠样品中六方球文石的位置、形状与大小。结果显示，其多分布于珍珠珠核部位，也可出现在珍珠表面。通过扫描电子显微镜进一步观察，珍珠表面上的六方球文石与文石的微形貌特征有较明显的区别。同时，还一并探讨了拉曼光谱在珍珠样品中出现的方向性效应以及有机色素产生的拉曼效应。

Study on Freshwater Non-nucleated Pearl by Miro-Laser Raman-Mapping Technology

In recent years, the study of vaterite in pearl becomes more and more popular. In the paper, the two mineral phases in the freshwater non-nucleated pearl samples are investigated according to the differences of characteristic Raman spectra between the aragonite and vaterite. The position, shape and size of the vaterite in the freshwater non-nucleated pearl samples are primarily confirmed by micro-laser Raman-mapping technology. The results show that the vaterite is usually distributed around the nucleus and few on the surface of the pearl samples. Through the scanning electron mieroscope（SEM）, there are different micro- morphology characteristics between vaterite and aragonite on the surface of the pearl sample. Meanwhile, the orientation effect of Raman spectra occurred in the pearl samples and Raman effect of the organic pigment have also been discussed.