Gemmological Characteristic of Nephrite with Dendrite Pattern from Dahua, Guangxi Province
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摘要: 含丰富“水草花”形态包裹体的软玉是广西大化软玉的一个独特品种,通过常规宝石学测试以及偏光显微镜、电子探针、红外光谱仪、拉曼光谱仪、X射线粉末衍射仪等仪器测试, 对广西大化“水草花”软玉的矿物组成及其内部进行测试分析。结果显示,该品种软玉的主要矿物组成为透闪石。透闪石根据晶体形态及大小分为两种:一类为纤维状变晶交织结构,颗粒粒度小且均一,质量分数大于95%;一类为片状-毛毡状变晶交织结构,颗粒粒度大,多呈团块,质量分数小于5%。广西大化软玉的“水草花”为不透明锰质氧化物,呈无定形态、粉末状和片状,由后期锰质氧化物充填进入透闪石微裂隙和颗粒间隙中形成的形态各异“水草花”状包裹体。Abstract: The nephrite with dendrite pattern from Dahua, Guangxi Province, is a special kind of nephrite jade. The nephrite with variety of dendrite pattern ("Shuicaohua") is an unique species of nephrite from Dahua, Guangxi Province. In this paper, the nephrite with variety of dendrite pattern was studied with gemmological tests, polarizing microscope, electron microprobe (EPMA), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy and X-ray diffraction(XRD). The gemmological testing results showed that the refractive index of samples is between 1.59 and 1.61 by point measurement and its average is 1.60. The density is between 2.89 and 2.94 and its average is 2.91. The surface of samples have variety of dendrite pattern("Shuicaohua").
By observing the mineral slices under polarizing microscope, the mineral component of the samples is tremolite. The textures of tremolite are classified in two types. One is fibrous intergrowth crystalloblastic texture, and the tremolite grains are distributed uniformaly and its content is more than 95% in general. The other is flaky intergrowth crystalloblastic texture, and the tremolite grains is distinctly larger and its content is less than 5%.
According to the electron microprobe (EPMA) test, the content of MnO in white-gray tremolite (without dendrite pattern) is between 0.21% and 0.35%, and the content of MnO of dendrite pattern is between 0.94% and 3.96%. It is concluded that the dendrite pattern ("Shuicaohua") is caused by MnO. The formation of dendrite pattern ("Shuicaohua") should be probably due to fracture filled with MnO.-
Keywords:
- nephrite /
- tremolite /
- "Shuicaohua" /
- MnO /
- Dahua, Guangxi Province
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[1] 李旭,於晓晋,王时麒.广西大化透闪石玉的发现及初步研究[J].岩石矿物学杂志,2011,30(S):47-52. [2] 杜季明.广西大化透闪石玉的宝石矿物学特征研究[D].北京:中国地质大学,2015. [3] 王宾,邵臻宇,廖宗廷,等.广西大化软玉的宝石矿物学特征[J].宝石和宝石学杂志,2012,14(3):6-11. [4] 徐立国,於晓晋,王时麒.广西大化东扛村透闪石玉的宝石学特征及成因[J].岩石矿物学杂志,2014(S1):55-60. [5] 王长秋,孙鹏,王时麒.大化墨玉的矿物学特征[J]. 岩石矿物学杂志,2014(S2):1-9. [6] 杨林.贵州罗甸玉矿物岩石学特征及成因机理研究[D].成都:成都理工大学,2013. [7] 张妮,刘自强,林春明,等.贵州罗甸透闪石质"花斑玉"的致斑物质组成及成因研究[A].珠宝与科技——中国珠宝首饰学术交流会论文集(2015)[C].北京:国土资源部珠宝玉石首饰管理中心,2015:4. [8] 支颖雪,廖冠琳,陈琼,等.贵州罗甸软玉的宝石矿物学特征[J].宝石和宝石学杂志,2011,13(4):7-13. [9] 朴庭贤,尹京武,闫星光,等. 贵州罗甸玉矿物学及成分特征[J]. 岩石矿物学杂志,2014(S1):7-18. [10] 李凯旋,姜婷丽,邢乐才,等. 贵州罗甸玉的矿物学及矿床学初步研究[J]. 矿物学报,2014,34(2):223-233. [11] 崔文元,杨富绪.和田玉(透闪石玉)的研究[J].岩石矿物学杂志,2002(S1):26-33. [12] 吴瑞华,李雯雯,白峰.新疆和田玉岩石学特征及其扫描电镜研究[J].岩石学报,1999,15(4):638-644. [13] 杨晓丹,施光海,刘琰. 新疆和田黑色透闪石质软玉振动光谱特征及颜色成因[J].光谱学与光谱分析,2012,32(3):681-685. [14] 张永旺,刘琰,刘涛涛,等.新疆和田透闪石软玉的振动光谱[J]. 光谱学与光谱分析,2012,32(2):398-401. [15] 那宝成,冷莹莹,李祥虎. 软玉致色元素的研究[J]. 超硬材料工程,2008,20(3):55-58. [16] 张勇,柯捷,陆太进,等. 黄色石英质玉石中"水草花"的物质组成研究[J]. 宝石和宝石学杂志,2012,14(3):1-5. [17] 闻辂,梁婉雪,章正刚,等.矿物红外光谱学[M]. 重庆:重庆大学出版社,1988:85-89.
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