绿松石的有机充填处理由来已久, 浸胶(丙烯酸酯类)、 注胶(环氧树脂类)两种充填方式已有大量研究, 冻胶(丙烯酸酯类)作为一种较新的充填方式, 研究基础较为薄弱。 以天然绿松石原料及其对应冻胶充填后的绿松石为研究对象, 结合处理所用冻胶材料, 通过常规宝石学测试、 红外光谱测试、 三维荧光光谱测试、 紫外-可见吸收光谱测试等测试技术, 对冻胶充填前后绿松石的宝石学特征和谱学特征进行系统的对比分析研究。 结果显示: 冻胶充填后, 绿松石的颜色和致密度得到明显提升, 表面有胶质物残留及白色“松花”现象, 冻胶充填绿松石在长波紫外灯下显示弱-中等的蓝色荧光, 短波下显示弱荧光, 胶质物残留位置发光明显, 而绿松石原料在长短波下均呈惰性; 冻胶原液的红外光谱显示CO伸缩振动峰［(1 722±5) cm-1］、 C-O伸缩振动峰［(1 156±5) cm-1］、 CC伸缩振动峰［(1 637±5) cm-1］, 还出现了苯环结构和C-OH的吸收峰, 表明其主要成分可能为含有苯环、 羧酸、 醇等结构的化合物与甲基丙烯酸酯的共聚物; 冻胶充填绿松石的红外光谱中出现了与冻胶原液对应的有机基团吸收峰, 可有效鉴别充填绿松石与原料; 三维荧光光谱测试显示: 绿松石原料在整个激发波长范围内没有出现明显的荧光中心, 冻胶充填绿松石均出现了发射波长在465、 445和410 nm附近的特征荧光中心, 激发波长范围为360～400 nm, 与冻胶原液的荧光中心相对应, 说明荧光由胶质物导致, 可作为冻胶充填的重要证据; 绿松石原料和冻胶充填绿松石的紫外-可见吸收光谱均符合天然绿松石的吸收特征, 说明冻胶充填过程中未添加有机染剂。

The organic filling treatment of turquoise has a long history, and there has been much research on two filling methods: immersion (acrylates) and injection (epoxy resins), while frozen jelly filling (acrylates) is a relatively new filling method with a weak research base. Using conventional gemological methods, FTIR, 3D fluorescence spectrometer and UV-VIS spectrum analysis, combined with the frozen jelly material used for the treatment, this paper presents a systematic comparative analysis of the gemological and spectroscopic characteristics of natural turquoise raw material and its corresponding frozen jelly-filled turquoise. The results showed that the color and density of turquoises were significantly enhanced by the frozen jelly filling, with glue residue and white “pine flower” on the surface; frozen jelly-filled turquoises showed weak-moderate blue fluorescence under the LW UV lamp and weak fluorescence under the SW, with obvious luminescence in the glue residue positions, while raw turquoises were inert under both LW and SW. The IR spectra of the frozen jelly solution showed CO stretching vibration peak ［(1 722±5) cm-1］, C-O stretching vibration peak ［(1 156±5) cm-1］, CC stretching vibration peak ［(1 637±5) cm-1］, benzene ring structure and C-OH absorption peaks, indicating that its composition may be a copolymer of compounds containing benzene ring, carboxylic acid, alcohol and other structures with methacrylate. The infrared spectrum of frozen jelly-filled turquoises showed the organic group vibrational peaks corresponding to the frozen jelly solution, effectively identifying filled turquoises from raw materials. 3D fluorescence spectra showed that raw turquoises did not appear obvious fluorescence centers throughout the excitation wavelength range, frozen jelly-filled turquoises all appeared characteristic fluorescence centers with emission wavelengths around 465, 445 and 410 nm, and excitation wavelengths in the range of 360～400 nm, corresponding to the fluorescence centers of the frozen jelly solution, indicating that the fluorescence was caused by glue, which can be taken as important evidence of frozen jelly filling. The UV-Vis absorption spectra of both raw turquoises and frozen jelly-filled turquoises were consistent with the characteristics of natural turquoises, indicating that no organic dyes were added during the jelly-filling process.