【作者】 郭清宏； 周永章； 曹姝旻； 丘志力； 徐志； 张余；

【Author】 GUO Qing-hong;ZHOU Yong-zhang;CAO Shu-yin;QIU Zhi-li;XU Zhi;ZHANG Yu;

【机构】 中山大学地球环境与地球资源研究中心； 广东省物料实验检测中心；

【摘要】 "广绿玉"是一种产于广东省广宁县的特色珍贵玉石材料。本文野外采集了绿、白、黄、黑等四类典型玉石原石,采用x粉末衍射、扫描电镜、红外光谱、差热分析、电子探针等多种测试方法,对玉石原石进行了全岩物相、主矿物显微形貌、矿物化学以及晶体结构分析。测试结果显示,"广绿玉"主要由2 M₁型绢云母组成,部分类型的主要和次要组分包括绿泥石和石英等。乙二醇饱和处理x粉末衍射和红外光谱分析显示绢云母结构中不含蒙脱石间层。差热分析指示玉石在中温区吸热谷的脱羟极值温度大于600℃,与水云母明显不同。扫描电镜显示绢云母类单矿物的微形貌多呈鳞片状,矿物排列组合沿长轴顺层穿插和定向交织,表现为叠层状或鳞片交织状微结构。电子探针成分分析表明绢云母矿物化学成分中Si、K、Al、Cr等含量较高,部分属含铬绢云母亚类,Cr可能是绿色和白色玉石主要的致色元素。更多还原

【Abstract】 The guangning jade is a precious type in various Chinese jades which is found in Guangning County,Guangdong province.Four types of different colored jade stones are sampled from field jade deposit,and which are used to study on the mineralogical characteristics of this special jade by XPD、SEM、DTA、IR and EMPA techniques.The data show that the 2M₁ sericite is the main mineral composite of all samples,and the chlorite is second.Both XPD and IR results indicate daunialite is not existed in the crystal structure of sericite.The analysis of DTA shows that the dehydroxylation temperature of samples is beyond 600℃,which is similar to sericite more than hydromica.The micro-texture of sericite occurs flake-shaped,and the minerals arranged along long-axis of crystal and interleaved by each other,showing overlapped and flake interleaved microstructure.The data of EMPA show that the chemical composition of sericite is rich in Si、K、Al and Cr.Especially,those rich in Cr can be subdivided and named Cr-bearing sericite.更多还原