激光拉曼光谱测试和田玉中的石墨  

Determination of Graphite in Hetian Jade by Laser Raman Spectroscopy

作　　者：王亚军 WANG Yajun(Jewellery Institute,Guangzhou Panyu Polytechnic,Guangzhou,Guangdong 511483,China;Jewelry and Jade and Jewelry Testing Center,Guangzhou Panyu Polytechnic,Guangzhou,Guangdong 511483,China)

机构地区：[1]广州番禺职业技术学院珠宝学院,广州511483 [2]广州番禺职业技术学院珠宝玉石及首饰检测中心,广州511483

出　　处：《中国无机分析化学》2024年第12期1698-1704,共7页Chinese Journal of Inorganic Analytical Chemistry

基　　金：国家自然科学基金资助项目(41502029);广州番禺职业技术学院科技类一般项目(2024KJ04)。

摘　　要：和田玉作为中国历史上著名的玉石,其矿物学特性和地质意义一直是学术界关注的焦点,为探究和田玉的矿物组成、石墨的特性及其地质意义,采用inVia显微共焦激光拉曼光谱仪测试获得和田玉的拉曼谱峰,主要的特征峰为121、159、178、223、249、369、395、674、931、1029和1060 cm^(-1),与透闪石的标准拉曼谱峰基本一致,表明该批和田玉所用玉料均为透闪石质玉。显微观察显示部分和田玉中呈现半自形粒状、带状、星点状、云雾状、薄片状、撕裂状的黑色次要矿物,经激光拉曼光谱测试表明该黑色次要矿物为石墨。对石墨拉曼光谱进行分峰拟合,获得谱峰的频移(Shiftwave)、半高宽(FWHM)、谱峰强度(I)和谱峰积分面积(A)等光谱信息,石墨G峰的位置1577.5~1581 cm^(-1)和半高宽16~31 cm^(-1),以及D1和G峰强度比值R在0.03~0.3,表明了其结晶程度较高。根据地质温度计算模型,通过石墨拉曼参数计算得出石墨经历的成矿温度主要集中在382~565℃,个别和田玉中的石墨显示不同的结晶度和成矿温度,表明可能来自不同的成矿阶段或地点,这一发现对于理解和田玉的地质形成过程具有重要意义。Hetian jade,celebrated in Chinese history,is noted for its distinctive mineralogical traits and geological importance.This study utilized laser Raman spectroscopy to explore the graphite inclusions within Hetian jade,aiming to elucidate its mineral composition and the graphite characteristics,which is vital for deciphering the jade′s geological origins and formation processes.The Raman spectral peaks of Hetian jade samples were analyzed by Renishaw inVia confocal Raman spectrometer.Microscopic observations complemented the identification and characterization of graphite inclusions by Raman spectroscopy.The main characteristic peaks were 121,159,178,223,249,369,395,674,931,1029 and 1060 cm^(-1),which were basically consistent with the standard Raman spectra of tremolite,indicating that the jade materials used in this batch of Hetian jade were tremolite jade.The microscopic observation showed that some Hetian jade exhibited semi-idiomorphic granular,band,star point,cloud,sheet and torn black minor minerals,and the laser Raman spectroscopy indicated that the black minor minerals were graphite.Spectral data were meticulously processed using Origin 2018 software for peak fitting,extracting specific spectral attributes such as wavenumber,full width at half maximum(FWHM),peak intensity,and integrated area.The peak fitting of the graphite Raman spectrum was carried out to obtain spectral information such as the frequency shift(Shiftwave),full width at half maximum(FWHM),peak intensity(I),and peak integral area(A)of the spectral peaks.The position of the graphite G peak(1577.5 cm^(-1) to 1581 cm^(-1))and the full width at half maximum(16 to 31 cm^(-1)),as well as the intensity ratio R of the D1 and G peaks(between 0.03 and 0.3),indicated that its degree of crystallization was relatively high.According to the Raman parameters of graphite,the metamorphic temperature ranged from 382 to 565℃,indicating a variety of formation conditions and potential disparities in the jade′s provenance or mineralization stages.It can be

关 键 词：激光拉曼光谱 和田玉 石墨 地质温度计 

分 类 号：O657.34[理学—分析化学] P575.4[理学—化学]