吉林蛟河橄榄石的宝石学特征  

Gemmological Characteristic of Peridot from Jiaohe,Jilin Province

作　　者：顾佳萌 赵庆华[2] 赖俊涛 王超[2] 尹作为[1] 

机构地区：[1]中国地质大学珠宝学院,湖北武汉430074 [2]郑州信息科技职业学院,河南郑州450046 [3]黎明职业大学材料与化学工程学院,福建泉州362000

出　　处：《宝石和宝石学杂志》2015年第5期24-31,共8页Journal of Gems & Gemmology

基　　金：国家自然科学基金项目(41202038);中央高校基本科研业务费专项资金基金项目(CUGW090229);中国地质大学实验技术研究项目--重点项目(CUG2013-23)

摘　　要：对来自吉林蛟河的5颗橄榄石样品,采用常规宝石学测试、USB4000光纤光谱仪、激光剥蚀电感耦合等离子体质谱仪(LA-ICP-MS)、拉曼光谱等现代测试方法对其进行深入分析。USB4000测试结果显示,橄榄石样品的主波长均落在550~590nm范围内,色调为黄色,为Fe^(2+)致色。LA-ICP-MS测试结果表明,橄榄石样品的主要成分为镁铁硅酸盐,其中2颗样品的化学式分别为(Mg_(1.780)Fe_(0.196)Mn_(0.003)Ca_(0.001))_(1.980)Si_(1.008)O_4和(Mg_(1.790)Fe_(0.208)Mn_(0.003)Ca_(0.002))_(2.111)Si_(0.997)O_4,Fo值均在90左右,表明其产地地幔为过渡型。根据CaO的质量分数判断橄榄石为地幔捕虏体产出。根据微量元素Ni的质量分数推导其母岩在地幔的熔融程度与张家口大麻坪地区橄榄石相近。拉曼光谱的定向测试表明,样品在垂直(100)、(010)、(001)三个方向的拉曼光谱有差异,其中垂直(001)方向的差异最大,而垂直(010)、(100)两个方向相似,这可能是由于不同方向Si—O振动不同造成的。拉曼光谱峰P1和P2的位置估测Fo值分别为92和88,与实测结果比较一致。Five peridot samples fromJiaohe, Jilin Province were tested in this paper. Conven tional gemmological tests, USB4000.LA-ICP-MS, and Raman spectrometer were used for the research. Dominant wavelengths ofperidot samples were measured in550-590nmrange according to USB4000,which show dominant hue is yellow colour and Fe is the colour-in- duced element. The results of I.A-IP-MS show that chemical formulas of two peridot sam- ples are （Mg1.780Fe0.196Mn0.003Ca0.001）1.980Si1.008O4 and （Mg1.790Fe0.208Mn0.003Ca0.002）2.111Si0.997O4 with their value of Fo approximately 90. It indicates that the origin mantle is transition type.According to the content of CaO, it can be judged that the output of peridot is from the man- tie xenolith. According to the content of Ni, the melting levelof the basahs from the mantle is similar to that from Da Maping in Zhang Jiakou. Raman spectrometer was used to test samples in different directions. Difference in the vertical （001） is the largest, which is main- ly due to the different direction of Si- O vibration while vertical （010） and vertical （100） are similar. We present a calibration for extracting olivine Fo contents （Fo=Mg/（Mg q- Fe） molar ratio; Fo, ） from the peak positions of this doublet, permitting estimates of chemi- cal composition from Raman spectra, and the value of Fo is 92 and 88.

关 键 词：橄榄石 颜色成因 元素分析 拉曼光谱 吉林蛟河 

分 类 号：TS93[轻工技术与工程]