中国绿松石矿产资源丰富, 是世界上主要的绿松石产出国家之一。 绿松石作为一种名玉, 以其独特的绿色及结构, 深受人们的喜爱, 也导致市场上出现了大量的优化处理品及仿制品。 在旅游珠宝进一步发展的同时, 打着“原产地”噱头的绿松石价格起伏非常大, 对比同一地点的天然及仿制品玉石, 在前人研究的基础上仍需要进一步积累数据。 论文以中国湖北竹山秦古镇小巴寨750矿洞采集的天然绿松石与购买于湖北竹山县城珠宝市场的绿松石仿制品为研究对象, 采用光学照片、 场发射扫描电镜及能谱、 红外和拉曼光谱等, 从颜色、 微形貌、 微成分微结构的角度开展对比研究。 研究结果表明, 天然绿松石样品的颜色多样, 呈“月白色—浅蓝色—蓝绿色—黄绿色—绿色—蓝色”的蓝绿色系列变化, 晶体颗粒十分细小, 呈微米级-纳米级, 可见短柱状、 层片状晶粒; 绿松石仿制品颜色单一, 常为较为呆板的绿色, 多为散漫分布的颗粒状集合体, 且颗粒多呈三方晶系、 方解石型结构; 天然绿松石主要成分为Al2O3 32.12%, P2O5 30.51%, CuO 10.75%, Fe2O3 5.57%等, 为铜铝磷酸盐矿物。 绿松石仿制品中主要元素组成为MgO 42.62%, Al2O3 2.66%, SiO2 2.66%等, 其成分是以碳酸镁为主的菱镁矿; 在红外光谱的对比研究中, 天然绿松石样品的红外光谱图的3 083～3 509 cm-1区域, 含有大量对应于ν(OH), ν(H2O)的红外吸收峰。 绿松石仿制品在2 922 cm-1处有对应于νas (CH2)的红外吸收谱峰, 该峰与其被染色有关。 这些红外吸收峰也是区分天然绿松石与仿制品的有效指纹峰; 在拉曼光谱图的对比研究中, 天然绿松石样品的拉曼光谱图中往往具有分别对应于ν(OH), ν(H2O), ν(PO4)的散射峰～3 470, ～3 270和～1 039 cm-1, 而绿松石仿制品不存在此类拉曼散射峰, 他们是区分天然绿松石及其仿制品的有效拉曼指纹峰。 基于颜色、 微成分、 微结构及振动光谱可以有效区分同一地区天然绿松石与其仿制品。 此类方法对于其他类型旅游珠宝与其仿制品的鉴定亦有重要的参考价值。

China is rich in turquoise mineral resources, and is one of the major producing countries in the world. As a kind of famous jade, turquoise is deeply loved by people with its unique colour of green and structure, which also leads to a large number of optimally treated products and imitations in the market. Compared to the study of turquoise and its imitations, the current researches on turquoise and its imitations need further data accumulation. In this paper, natural turquoise and its typical imitations from Zhu County in Hubei province were studied. Using optical photograph, field emission scanning electron microscope and energy spectrum, infrared and Raman spectra, a comparative study was conducted from the perspective of color, microstructure and microstructure. Research results showed that natural turquoise’s color varies with, the “white-light blue-light green-yellow-green-blue” series of change; the crystal particles are very small, and they are micro-sized to nano-scale, and short columnar and lamellar grains can be seen. The colors of turquoise’s imitations are single, often for the green, and it’s mostly scattered granular aggregate, and its size and appearance are not uniform. Natural turquoise mainly contains Cu, Al, P, O and other elements, and occasionally contains a small amount of Zn, Fe and other elements, therefore, it is mainly copper and aluminum phosphate minerals. Most particles of the turquoise imitations mainly contain of C, O, Mg and occasionally contain a small amount of Ca element, therefore, it’s mainly composed of magnesium carbonate magnesite. In the comparative study of infrared spectrum, the infrared spectrum of natural turquoise 3 083～3 509 cm-1 area contains a large number of infrared absorption peaks corresponding to the ν(OH) and ν(H2O). There were infrared absorption spectrum peak corresponding to νas (CH2), which is related to dyeing. These infrared absorption spectrum peaks are also the effective Raman fingerprint peaks of natural turquoise and turquoise imitation. In the study of contrasting Raman spectrograms, there were usually scattering peaks of ν(OH), ν(H2O), ν(PO4) at ～3 470, ～3 270, ～1 039 cm-1 related to natural turquoise when the turquoise imitation was not. So, they are all effective Raman fingerprint peaks between natural turquoise and turquoise imitation. Based on color, microstructure, microstructure and vibration spectrum, natural turquoise and its imitations can be distinguished. At the same time, this kind of method also contributes to distinguishing the other kinds of jade and the treatment ones.