新疆和田硬水铝石-蓝宝石谱学研究  

Spectra Characterization of Diaspore-Sapphire From Hotan,Xinjiang

作　　者：刘佳 郑亚龙 王成博 尹作为 潘少逵 LIU Jia;ZHENG Ya-long;WANG Cheng-bo;YIN Zuo-wei;PAN Shao-kui(Gemmological Institute,China University of Geosciences(Wuhan),Hubei Gems and Jewellry Engineering Technology Research Center,Wuhan 430074,China)

机构地区：[1]中国地质大学(武汉)珠宝学院,湖北省珠宝工程技术研究中心,湖北武汉430074

出　　处：《光谱学与光谱分析》2024年第1期176-180,共5页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(41973032);湖北省珠宝工程技术研究中心科研项目(CIGTXM-03-202001)资助。

摘　　要：研究一种以籽料形式出现的被称为蓝色和田玉的宝石,其产量稀少,市场价格极高。因无前人研究,无规范命名,交易市场中其商业名称混乱。使用静水称重确定其相对密度为3.85 g·cm^(-3),长波紫外灯下,白色矿物部分呈橘色荧光,其他部位荧光为惰性。经显微观察,样品可见平直蓝色-白色色带、角状蓝色-白色色带以及深蓝-浅蓝色带,并可见大量白色脉状矿物。经正交偏光及微分干涉观察,确定脉状矿物与基底为不同矿物,且形成于基底之后。使用显微红外光谱仪,确定蓝色基底和白色色带红外吸收峰位于812/817、 652/655、 613/620 cm^(-1),符合刚玉特征振动;脉状矿物可见3 019、 2 950、 2 129、 1 990、 1 121、 1 030、 799、 733、 648和598 cm^(-1)吸收,符合硬水铝石特征振动。通过显微紫外-可见-近红外分光光度计测定样品不同部位吸收光谱,其中白色色带未见明显吸收,脉状矿物见Fe^(3+)的d电子跃迁^(6)A_(1)→^(4)E,^(4)A_(1)(^(4)G)导致的429和453 nm吸收及OH振动引起的1 810、 2 030和2 235 nm吸收,蓝色基底部位分别见Fe^(3+)的d电子跃迁^(6)A_(1)→^(4)E,^(4)A_(1)(^(4)G)、 Fe^(2+)-Ti^(4+)离子对电荷转移及Fe^(2+)-Fe^(3+)离子对电荷转移导致的421/418、 562/566和702/709及868/889 nm吸收,且随着颜色加深,蓝区421 nm吸收发生蓝移,500~900 nm吸收发生红移,且吸收峰积分面积增加。通过X射线粉晶衍射定量分析确定样品中蓝宝石占比约66.9%,硬水铝石占比约33.1%,根据国家标准珠宝玉石名称(GB/T 16552—2017),建议命名为硬水铝石-蓝宝石。This paper studies a kind of seed material gemstone called“blue Hotan jade”with sparse output and high marketing price.Due to the deficiency of previous research and standardized naming,its business name is confused in the trading market.Hydrostatic weighing method determines The relative density of 3.85 g·cm^(-3).Only the white mineral part shows orange fluorescence under the long-wave ultraviolet lamp.Through microscopic observation,straight a blue-white color zone,coniform blue-white color zone,irregular blue zone and many white vein minerals can be seen.Through observation by orthogonal polarization and differential interference,it is determined that the vein minerals are different from the substrate and formed after the substrate.It is determined that the infrared absorption peaks of blue substrate and white zone mineral are located at 812/817,652/655 and 613/620 cm^(-1),which conforms to the characteristic vibration of corundum;3019,2950,2129,1990,1121,1030,799,733,648,598 cm^(-1)absorptions of vein minerals conform to the characteristic vibration of diaspore.The absorption spectra of different parts of the sample were measured by micro UV-VIS-NIR spectrophotometer,in which no obvious absorption was found in the white color zone;429 and 453 nm absorption caused by Fe^(3+)d electron transition^(6)A_(1)→^(4)E,^(4)A_(1)(^(4)G)and 1810,2030 and 2235 nm absorption caused by OH vibration were found in the vein minerals;421/418,562/566,702/709 and 868/889 nm absorption caused by Fe^(3+)d electron transition^(6)A_(1)→^(4)E,^(4)A_(1)(^(4)G),Fe^(2+)-Ti^(4+)ion pair charge transfer and Fe^(2+)-Fe^(3+)ion pair charge transferwere observed on the blue substrate.As the color deepens,the blue region 421 nm absorption occurs blue shift,500~900 nm absorption occurs red shit,and the absorption peak integral area increases according to the quantitative analysis of the XRD pattern,sapphire accounts for about 66.9%,and diaspore about 33.1%.According to the national standard named jewellry and jade(GB/T 16552—2017),it

关 键 词：“蓝色和田玉” 硬水铝石-蓝宝石 红外光谱 显微紫外可见近红外吸收光谱 

分 类 号：P575[天文地球—矿物学]