Composition and distinction of white nephrite from Asian deposits
作者单位：State Key Laboratory of Lithospheric EvolutionInstitute of Geology and GeophysicsChinese Academy of Sciences GeoZentrum NordbayernUniversitt Erlangen-NürnbergSchlossgarten 5aD-91054 ErlangenGermany. School of Gem StudiesChina University of Geoscience Gem Appraisal Center of Peking University GeoZentrum NordbayernUniversitt Erlangen-NürnbergSchlossgarten 5aD-91054 ErlangenGermany
会议名称：《中国科学院地质与地球物理研究所2013年度（第13届）学术年会》
会议日期：2014年
学科分类：081803[工学-地质工程] 08[工学] 0818[工学-地质资源与地质工程]
基 金：supported by China Scholarship Council, the national Natural Science Foundation of China(Grants No.41173009,41222023) State Key Laboratory of Lithospheric Evolution,IGG-CAS
关 键 词：tremolite white nephrite electron microprobe analysis Asian nephrite deposits archaeology
摘 要：The major and minor element compositions and textures of white nephrite samples from 6 different deposits including Xiaomeiling district(Jiangsu province,China),Luanchuan district(Henan province,China),Hetian district(Xinjiang province, China),Geermu district(Qinghai province,China),Chuncheon district(Korea) and Baikal district(Russia) were investigated by means of optical and electron microscopy and wavelength-dispersive electron microprobe analysis(EMPA).The white nephrites from all deposits display similar fine-grained textures and white ***,as the main mineral of the white nephrite,roughly has a similar composition in all samples mcluding high amounts of Si,Mg,Ca,and low Fe ***,the samples show small but specific differences that allow distinguishing samples from different *** of sample N1 from Xiaomeiling has the most extreme composition,because it contains considerably more F(average 1.8wt.%) than all other samples,and also shows the highest Na and K *** tremohte of white nephrite N2 from Luanchuan shows the highest Fe content of the sample *** Ca content is also comparably high,while Na,K,F,and Al concentrations are below the detection *** of sample N3 from Hetian is characterized by the second highest F content(0.4-0.7 wt.%) and a stoichiometric Si *** of sample N4 from Geermu has the highest nonstoichiometric Si content(～8.1 Si pfu(per formula unit)) and a relatively high Ca content(～2.0 Ca pfu).Other elements(Na,K,F,and Al) are below or close to the detection *** tremohte of Korean sample N5 from Chuncheon can be distinguished on the basis of its low F content(～0.2 wt.%) and its characteristic mosaic *** though sample N6 from Russia has no unique compositional feature that distinguishes it from other samples,it can be distinguished from the other samples if all textural and compositional data are *** study demonstrates that fluorine of tremohte is one of