西藏错那洞萤石的宝石矿物学特征  

Gemmological and Mineralogical Characteristics of Fluorite from Cuonadong,Xizang,China

作　　者：邢志芬 申佳奇 许博 王硕[1] XING Zhifen;SHEN Jiaqi;XU Bo;WANG Shuo(School of Earth Science and Resources,Chang’an University,Xi’an 710054,China;School of Gemmology,China University of Geosciences,Beijing 100083,China)

机构地区：[1]长安大学地球科学与资源学院,陕西西安710054 [2]中国地质大学(北京)珠宝学院,北京100083

出　　处：《宝石和宝石学杂志(中英文)》2025年第1期21-29,共9页Journal of Gems & Gemmology

基　　金：陕西省自然科学基金项目(2023-JC-YB-222)。

摘　　要：西藏隆子县错那洞Be-Sn-W多金属矿床产出的萤石色彩瑰丽,目前关于该矿床的研究已取得显著成果,但针对其产出萤石的宝石矿物学特征研究资料相对较少。本研究收集了4块西藏错那洞萤石样品,采用常规宝石学仪器、偏光显微镜、傅里叶变换红外光谱仪(FTIR)、拉曼光谱仪、紫外-可见光谱仪(UV-Vis)、X射线荧光光谱仪(XRF)和电感耦合等离子体质谱仪(ICP-MS)等对其进行测试分析。结果表明,西藏错那洞萤石样品内部具有大量流体包裹体以及长柱状透闪石矿物包裹体;主要成分为CaF_(2),并含有稀土元素和金属元素等,稀土元素总含量介于4.03~51.36μg/g之间,整体偏低,绿色萤石样品中稀土元素总含量以及La、Ce、Pr、Nd、Sm、Gd、Dy的含量显著高于其他样品;红外光谱和拉曼光谱中均显示出萤石的特征峰,部分样品在拉曼光谱中还显示稀土离子光致发光谱峰;综合化学成分和紫外-可见光谱特征,推测绿色萤石的颜色主要由Sm^(2+)引起,并可能受到Y^(3+)和Ce^(3+)的影响共同作用形成,深粉色萤石的颜色则由YO_(2)色心导致。The fluorite from the Cuonadong Be-Sn-W polymetallic deposit in Longzi County,Xizang,China,exhibits remarkable colouration.Previous studies on Be-Sn-W polymetallic deposits have yielded significant results,however,research on the gemmological characteristics of the fluorite from Cuonadong remains relatively limited.In this study,four fluorite samples from Cuonadong,Xizang,China were collected and analyzed using conventional gemmological test instruments,polarizing microscope,Fourier transform infrared spectrosmeter(FTIR),Raman spectrometer,ultraviolet-visible(UV-Vis)spectrosphotometer,X-ray fluorescence(XRF)spectrometer,and inductively coupled plasma mass spectrometry(ICP-MS).The results indicate that the fluorite samples contain numerous fluid inclusions and long columnar tremolite mineral inclusions.The samples are primarily composed of CaF_(2) and contain rare earth elements(REEs)and metal elements.The total REE content(4.03-51.36μg/g)is relatively low.Notably,the total REE content and the concentrations of La,Ce,Pr,Nd,Sm,Gd and Dy in green fluorite sample are significantly higher than those in other samples.The characteristic peaks of fluorite samples are evident in both infrared spectra and Raman spectra.Some samples exhibit photoluminescence peaks of rare earth ions in Raman spectra.Based on the chemical compositions and UV-Vis spectral characteristics,it is speculated that the green colouration of fluorite sample is primarily caused by Sm^(2+),with possible contributions from Y ^(3+)and Ce ^(3+).The deep pink colouration of fluorite sample is attributed to the YO_( 2) colour center.

关 键 词：萤石 宝石矿物学特征 谱学特征 致色机理 西藏错那洞 

分 类 号：TS93[轻工技术与工程]