Mineral Structure and Mineralization Mechanism of Serpentine Jade from Luchuan, Guangxi Province
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摘要: 应用外束质子激发X射线荧光光谱法、X射线衍射、激光拉曼光谱、扫描电子显微镜等无损分析技术,对广西陆川蛇纹石玉的成分、物相和结构进行分析。X射线衍射结果显示样品的衍射峰主要位于0.724、0.456、0.362、0.248、0.153和0.150 nm处,表明陆川蛇纹石玉主要矿物成分是蛇纹石,同时伴生方解石矿物与蛇纹石形成穿插交织结构。成矿机理分析表明,陆川蛇纹石玉是由白云质大理岩热液交代作用形成的,和广东的信宜玉均属于富镁碳酸盐型蛇纹石。拉曼光谱显示叶蛇纹石的特征峰位于229、376、457、686和1046 cm-1处,纤蛇纹石的特征峰位于228、345、386、624、690和1102 cm-1处,通过激光拉曼光谱可以快速区分陆川蛇纹石玉中纤蛇纹石和叶蛇纹石两种不同结构的蛇纹石亚种。Abstract: The nondestructive analysis techniques of Proton Induced X-ray Emission (PIXE), X-ray Diffraction (XRD), Laser Raman Spectroscopy (LRS) and Scanning Electron Microscopy (SEM) were applied to analyze the chemical composition and mineral structure of serpentine jade from Luchuan, Guangxi Province. The major XRD bands of the samples located at 0.724, 0.456, 0.362, 0.248, 0.153 and 0.150 nm, indicate that the major mineral of Luchuan jade is serpentine. Meanwhile, interpenetration texture was formed between serpentine and associated calcite. Luchuan serpentine jade was formed by hydrothermal metasomatism from dolomitic marble, and both Luchuan Jade and Xinyi Jade belong to Mg-rich carbonate type serpentine. Raman characteristic bands of antigorite located at 229, 376, 457, 686 and 1046 cm-1 while that of chrysotile occurred at 228, 345, 386, 624, 690 and 1102 cm-1. Therefore, the Raman spectroscopy can be used to identify chrysotile and antigorite of the serpentine minerals of Luchuan jade.
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致谢: 感谢中国科学院上海光学精密机械研究所李青会副研究员提供陆川蛇纹石玉样品。感谢复旦大学承焕生教授在PIXE测量中的指导与帮助,感谢马波老师在实验中提供的支持与帮助。
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表 1 样品常量元素PIXE分析结果
Table 1 Analytical results of major and minor elements in the samples determined by PIXE technique
样品编号 测试点 wB/% Na2O MgO Al2O3 SiO2 P2O5 K2O CaO TiO2 Cr2O3 MnO Fe2O3 CoO NiO CuO ZnO 10LC-1a 浅黄绿色 1.21 46.96 1.46 49.47 0.27 0.07 0.15 0.03 0 0 0.37 0 0 0 0.02 10LC-1b 白色 2.19 43.92 0.35 45.76 0.06 0.04 7.01 0.01 0.02 0 0.48 0 0 0 0 10LC-2a 黄绿色 2.28 46.46 1.01 48.6 0.17 0.02 0.06 0 0.01 0.01 1.37 0 0.01 0 0 10LC-2b 白色 0 18.48 0.14 12.13 0 0 68.83 0 0 0 0.43 0 0 0 0 10LC-3 黄绿色 0.80 40.43 0.80 39.5 0.27 0.19 17.12 0 0.05 0.02 0.61 0 0 0.02 0 注:蛇纹石的化学式为Mg6[Si4O10](OH)8,理论化学组成 (质量分数) 中MgO为43.0%,SiO2为44.1%,H2O为12.9%。 表 2 块状样品的X射线衍射数据
Table 2 Data of bulk samples by X-ray diffraction patterns
样品编号 hkl 001 110 002 104 104 131 132 203 152 060 411 10LC-1a d 7.24 4.56 3.62 3.01 2.48 2.14 1.79 1.53 1.50 1.30 I 33.9 30.4 31.6 25.9 100 20.6 7.3 50.3 27.2 19 10LC-2a d 7.11 4.51 3.60 3.00 2.48 2.13 1.78 1.53 1.50 1.30 I 100 19 66.7 17.3 29.6 8.7 5.4 17.9 11.3 6.3 10LC-3 d 7.44 4.63 3.68 3.05 2.88 2.53 2.15 1.56 1.54 1.31 I 100 21 73.4 72.5 14.8 32.8 10.5 11.4 20.5 11.5 -
王时麒, 赵朝红, 于光, 员雪梅, 段体玉.中国岫岩玉[M].北京:科学出版社, 2007: 46-51. 邹天人, 郭立鹤, 於晓晋.中国主要玉石类型及产地[J].矿床地质, 1996, 15(Z1): 79-92. http://www.cnki.com.cn/Article/CJFDTOTAL-KCDZ1996S1030.htm Cheng H S, Zhang Z Q, Zhang B, Yang F J. Non-destructive analysis and identification of jade by PIXE [J]. Nuclear Instruments and Methods in Physics Research Section B, 2004, 219-212: 30-34. https://www.researchgate.net/publication/229176640_Non-destructive_analysis_and_identification_of_jade_by_PIXE
Rinaudo C, Gastaldi D, Belluso E. Characterizatioin of chrysotile, antigorite and lizardite by FT-Raman spectroscopy [J]. The Canadian Mineralogist, 2003, 41: 883-890. doi: 10.2113/gscanmin.41.4.883
Kloprogge J T, Frost R L, Rintoul L. Single crystal Raman microscopic study of the asbestos mineral chrysotile [J]. Physical Chemistry, 1999, 1: 2559-2564. https://www.researchgate.net/publication/253917280_Single_crystal_Raman_microscopic_study_of_the_asbestos_mineral_chrysotile
罗红宇, 王春生, 廖尚宜.宝石中常见过渡金属离子致色的理论解释[J].岩石矿物学杂志, 2004, 19(6): 177-181. http://www.cnki.com.cn/Article/CJFDTOTAL-YSKW200402009.htm Hess H H, Smith R J, Dengo G. Antigorite from the vicinity of Caracas, venezuela [J]. American Minerologist, 1952, 6: 68-75. http://rruff.info/doclib/am/vol37/AM37_68.pdf
Vyasa Rao A N, Murty M S. A study of the serpentinisation in the Vempalle dolomitic limestones near Pulivendala, Cuddapah District [J]. Journal of Earth System Science, 1980, 1: 17-22. doi: 10.1007/BF02841515
李娟.南方玉[J].广东有色金属地质, 1999(1): 49-50. 关崇荣, 陈宇.广东省信宜市南方玉矿矿床地质特征[J].西部探矿工程, 2005(12): 152-153. http://www.cnki.com.cn/Article/CJFDTOTAL-XBTK200512074.htm 赵珊茸.结晶学及矿物学[M].北京:高等教育出版社, 2004: 372-374. Groppo C, Rinaudo C, Cairo S, Gastaldi D, Compagnoni R. Micro-Raman spectroscopy for a quick and reliable identification of serpentine minerals from ultramafics [J].European Journal of Mineralogy, 2006, 18: 319-329. doi: 10.1127/0935-1221/2006/0018-0319