云南金顶异极矿晶体化学特征与颜色成因探讨  

Crystal Chemistry and Color Genesis of the Hemimorphite from Jinding Pb-Zn Deposit, Yunnan Province

作　　者：刘琰[1,2] 邓军[1,2] 王庆飞[1,2] 周应华[2] 

机构地区：[1]中国地质大学地质过程与矿产资源国家重点实验室,北京100083 [2]中国地质大学岩石圈构造,深部过程及探测技术教育部重点实验室,北京100083

出　　处：《高校地质学报》2005年第3期434-441,共8页Geological Journal of China Universities

基　　金：教育部跨世纪优秀人才培养计划和科学技术研究重点项目(03178;01037);国家自然科学基金(40304007;40172036)

摘　　要：为研究云南金顶铅锌矿床中异极矿谱学特征和颜色成因,利用湿法化学全分析、振动光谱仪、X光粉晶衍射仪和电子探针对5组异极矿样品谱学特征和化学成份进行研究。湿法化学全分析得出了异极矿的化学成份,成份中出现了可能致色的铜、铁和镍元素;X光粉晶衍射和振动光谱分析得出异极矿晶胞参数和特征谱线表明样品蓝色和白色环带均为异极矿,5组样品的平均晶胞参数为:a=0.8372nm,b=1.0702nm,c=0.5116nm;红外光谱测试中获得了未见报道的452cm^(-1)以下异极矿晶体结构吸收峰,同时分析了异极矿中的结构水、结晶水吸收谱带;对红外光谱和拉曼光谱中的各吸收谱带和特征峰进行了归属。通过电子探针、红外光谱、拉曼光谱测试和分析认为异极矿的蓝色与Cu^(2+)的类质同像替代有关,白色异极矿不含铜元素,白色和蓝色异极矿结构相似,异极矿玻璃光泽和土状光泽与其含有较多的结晶水有关。For the purpose of understanding the spectra characteristics and color-causing mechanism of the hemimorphite found in the oxidation zones of Jinding Pb-Zn deposits, 5 techniques were applied to analyse this mineral： wet chemical analysis, IR, LRM, XRD and EMPA. The complete chemical compositions of the mineral were obtained and large emphasis was put on the possible color causing elements, such as Cu, Fe and Ni. The white and blue hemimorphite samples were tested by XRD and IR to reveal if there are other minerals intermingled with hemimorphite. At the same time, the cell parameters were calculated. The average cell parameters are a = 0. 8372nm, b = 1. 0702nm, and c =0.5116nm. The absorption bands of crystal structure in the range of infrared spectra （180 -452 cm^-1） were obtained, which were not reported before. Meanwhile, the structure, the structure water and crystal water were studied through infrared spectra. The peaks and absorption bands of infrared and Raman spectra were assigned. Generally, partial substitutions of Cu^2＋ for Zn^2＋ may cause the blue color of the hemimorphite. In addition, the blue and white hemimorphites share the same crystal structure based on XRD, IR and LRM. The glass luster and dust luster of the hemimophite are related with the large amount of crystal water in it.

关 键 词：异极矿 晶体化学 振动光谱 颜色成因 金顶铅锌矿 云南 

分 类 号：P578.952[天文地球—矿物学]