古代玉石白化机理解析——以三星堆遗址出土部分玉器为例  

Analysis of the whitening mechanism of ancient tremolite jade:taking some of the jades excavated from the Sanxingdui site as examples

作　　者：王云鹏[1,2] 刘建成 李志敏[1] 王凤娇[3] 鲁海子 方辉 马清林[4] WANG Yunpeng;LIU Jiancheng;LI Zhimin;WANG Fengjiao;LU Haizi;FANG Hui;MA Qinglin(Joint International Research Laboratory of Environmental and Social Archaeology,Shandong University,Qingdao 266237,China;Shandong Provincial Cultural Relics Conservation,Restoration and Identification Center,Jinan 250014,China;Sichuan Provincial Institute of Cultural Relics and Archaeology,Chengdu 610042,China;School of Materials Science and Engineering,Beijing University of Chemical Technology,Beijing 100029,China)

机构地区：[1]山东大学环境与社会考古学国际合作联合实验室,山东青岛266237 [2]山东省文物保护修复与鉴定中心,山东济南250014 [3]四川省文物考古研究院,四川成都610042 [4]北京化工大学材料科学与工程学院,北京100029

出　　处：《文物保护与考古科学》2024年第5期17-33,共17页Sciences of Conservation and Archaeology

基　　金：山东省青年文博人才培养项目;四川省科技计划重点研发项目(2024YFFK0125)资助。

摘　　要：中国古代出土玉器常伴有白化现象,此现象在三星堆遗址出土玉石器中较为常见。本研究采用X射线衍射仪、激光共聚焦显微拉曼光谱仪、傅里叶变换红外光谱仪、同步热分析仪等分析三星堆遗址出土白化玉器。结果显示三星堆遗址出土白化玉器主要物相为方解石及透辉石——透辉石可由透闪石受热转化而成,玉器白化与受热有关。透闪石玉由高温热液流经镁质碳酸岩通过交代作用而形成,镁质碳酸盐岩中富含晶包有机质,推测透闪石玉中同样含有晶包有机质。本研究中玉石的荧光光谱及加热、溶出等模拟试验均证明了这一推论。方解石与透闪石玉内均含有分散有机质,玉石白化不仅取决于玉石结构变化,还与玉内分散有机质流失有关。The phenomenon of whitening is frequently observed in ancient jade artifacts unearthed in China,with a particularly high prevalence at the Sanxingdui site.In this study,X-ray diffraction(XRD),laser confocal micro-Raman spectrometry(Raman),Fourier transform infrared(FTIR)spectrometry,and simultaneous thermal analysis were used to analyze whitened jades excavated from the Sanxingdui site.The XRD results indicate that the primary phases of the whitened jades were calcite and diopside—the latter can be generated through the transformation from tremolite with heat.The Raman result indicates the presence of a pronounced hump-shaped fluorescence background for the jades.This type of fluorescence is more prevalent in carbonate minerals with elevated levels of sedimentary organic matter.The formation of tremolite jade is a consequence of high-temperature hydrothermal fluid flowing through magnesium carbonate rock.During the diagenetic transition,the dispersed organic matter in magnesium carbonate rock is partially retained in the tremolite.Carbonatite minerals and tremolite jade contain a certain amount of crystal-enclosed organic matter in addition to the presence of adsorbed organic matter.The content of the crystal-enclosed organic matter in tremolite jade is relatively lower,with a release temperature of 900-1150℃.This organic matter is primarily composed of ammonium or magnesium salts of waxes and resins.Tremolite jade loses its greasy luster and gets whitened after the loss of crystal-enclosed organic matter.The oxidation or polymerization of the dispersed organic matter within the jade will increase the carbonyl(C=O)functional groups in the organic molecules,and the increase of unsaturated bonds will cause a conjugation effect of the organic molecules within the jade,with the fluorescence intensity being geometrically increased.Modern coal petrology employs a range of technologies,such as the fluorescence one,to microscopically identify visible dispersed organic matter in sedimentary rocks through optical micro

关 键 词：透闪石玉 沉积有机质 晶包有机质 荧光光谱 

分 类 号：K876.8[历史地理—考古学及博物馆学]