绿松石及其常见仿制品的矿物学及谱学特征研究  

Mineralogical and Spectral Characteristics of Turquoise and Its Common Imitations

作　　者：许多 周征宇[1] XU Duo;ZHOU Zhengyu(School of Ocean and Earth Science,Tongji University,Shanghai 200092,China)

机构地区：[1]同济大学海洋与地球科学学院,上海200092

出　　处：《宝石和宝石学杂志（中英文）》2024年第S01期13-15,共3页Journal of Gems & Gemmology

基　　金：珠宝玉石标准样品库科技基础条件平台;上海市科学技术委员会科研攻关项目(项目代码1350296T001)。

摘　　要：绿松石在全世界有着悠久的历史,对于中国文化的起源与发展有着巨大影响。而到了现代,绿松石因其颜色、质地、历史寓意以及宗教韵味而在全世界风靡,绿松石的造假手段也在不断更新,绿松石市场的健康发展受到冲击。本研究选取来自矿区、厂家与可信渠道购得的绿松石及其相似品,通过这些样品研究天然绿松石样品与绿松石仿制品的矿物谱学特征,以期系统性地分析天然绿松石与绿松石仿制品的谱学特征差异,并为鉴定提供科学依据。本文主要通过常规宝石学测试、红外光谱、拉曼光谱、紫外-可见光谱与能谱分析等现代测试技术对天然绿松石及其仿制品样品进行系统的矿物谱学研究,得出以下结论。(1)天然绿松石样品的密度2.45~2.75 g/cm^(3),折射率1.61~1.63,w(Al_(2)O_(3))为33.84%~34.03%,w(P_(2)O_(5))为29.97%~33.69%,w(Fe_(2)O_(3))为2.60%~3.25%,w(CuO)为8.19%~9.13%。(2)结构水、结晶水与磷酸根基团的振动频率决定了天然绿松石的红外吸收光谱与拉曼光谱。其中,由结构水的伸缩振动致红外吸收峰出现在3508 cm^(-1)和3463 cm^(-1)处,拉曼光谱谱峰则出现在3496、3471、3448 cm^(-1)处;弯曲振动致红外吸收峰出现在841 cm^(-1)和784 cm^(-1)处,拉曼光谱谱峰出现在812 cm^(-1)处。结晶水的伸缩振动致红外吸收峰出现在3287 cm^(-1)和3086 cm^(-1)处,拉曼光谱谱峰出现在3265 cm^(-1)和3069 cm^(-1)处;弯曲振动致红外吸收峰出现在1652 cm^(-1)处,拉曼光谱出现在1618 cm^(-1)处。磷酸根基团的伸缩振动致红外吸收峰出现在1112 cm^(-1)和1060 cm^(-1)处,拉曼光谱出现在1159、1102、1039、937 cm^(-1)处;弯曲振动致红外吸收峰出现在648、569、483 cm^(-1)处,拉曼光谱出现在643、589、547、470、414 cm^(-1)处。天然绿松石的紫外-可见光谱发现有4个吸收峰,分别是位于267 nm处由O^(2-)-Fe^(3+)的电荷转移所引起的吸收峰,位于430 nm处由Fe的水合离子�This article mainly used modern testing techniques such as conventional gemmological tests,infrared spectrometer,Raman spectrometer,ultraviolet visible spectrometer,and energy spectrum analysis to systematically study the mineralogical and spectra characteristics of the turquoise and its imitations purchased from mining areas,manufacturers,and trusted channels.We have come to the following conclusion.The density of natural turquoise is between 2.45-2.75 g/cm^(3),and the refractive index is between 1.61-1.63.The vibration frequencies of structural water,crystalline water,and phosphate groups determine the infrared absorption spectra and Raman spectra of natural turquoise.The infrared spectrum tests show the IR absorption peaks around 3508,3463,3287,3086,1652,1112,1060,841,784,648,569 cm^(-1)and 483 cm^(-1);Raman spectrum tests show the peaks around 3496,3471,3448,3265,3069,1618,1159,1102,1039,937,812,643,589,547,470 cm^(-1)and 414 cm^(-1);The absorption peaks appear near 267,430,670 nm and 799 nm in the UV visible spectrum.There are many varieties of turquoise’s imitation products,commonly seen in the market mainly including trihydrate alumina,barite,magnesite,calcite and mineral mixtures.The most effective and rapid method for distinguishing them from natural turquoise is infrared absorption spectrum of turquoise in the range of 3600-3000 cm^(-1)and 1200-900 cm^(-1).The presence of an absorption peak at 430 nm in the UV visible spectrum and the presence of Cu and Fe of colouring elements in turquoise can be used as auxiliary evidence.

关 键 词：绿松石 仿制品 红外光谱 拉曼光谱 

分 类 号：TS933[轻工技术与工程]