Microstructure Characteristic of Amber from Myanmar
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摘要: 琥珀是一种有机宝石,它在宝石学、地质学、古生物学等多个学科领域都有重要的研究价值。目前琥珀的研究工作主要集中在宝石学特征及光谱特征,仅有较少的波罗的海蜜蜡和多米尼加琥珀微观形貌特征,缅甸琥珀作为重要的琥珀来源之一,具有很大的探索空间。以缅甸琥珀为研究对象,采用红外光谱、扫描电子显微镜等测试方法对其显微形貌特征进行观察,分析了缅甸蜜蜡致密程度的影响因素,推测了缅甸根珀结构的形成原因、棕珀流淌纹红色斑点的形成机制。结果显示,缅甸根珀结构可分为致密和疏松两大类,致密结构表现为棉絮状、纤维状特征;疏松结构呈斑驳状特征。在缅甸根珀的显微结构中均可观察到不规则排列的椭圆状气泡分布在片状基质中;致密结构根珀中气泡大小均匀,同时还可观察到均匀分布的直径为10~30 μm的空管,沿空管周边可见气泡聚集现象;疏松结构根珀中气泡分散且大小不等,小气泡直径为1~2 μm,大气泡直径可达到11 μm。实验结论:(1)气泡面积所占的比例及气泡分布的均匀性与根珀的致密结构呈正相关关系,即气泡面积比例越大,气泡直径越小,分布越均匀,根珀结构越致密,反之则疏松;(2)依据气泡的形态、大小和分布特征,推测缅甸根珀中的气泡与自身携带的萜烯类挥发组分有关;(3)致密结构根珀中的空管,形态似龟裂纹,成因可能与树脂在差异性、阶段性分泌时因快速凝固产生细小的龟裂纹有关,气泡可沿压力低的裂隙通道逃逸并富集;(4)缅甸琥珀中特征的褐红色点状包裹体以浸染形态存在于琥珀基质中,并未发现前人报道的外来物质,而是在红色斑点分布区域具有鳞片状结构,且与周围的致密片状结构有明显的差异,推测红色点状包裹体的成因可能与琥珀中的挥发成分的差异有关,且红色点状包裹体形成的流淌纹也是挥发组分沿一定方向逃逸的表现。Abstract: Amber is an organic gem, which has important research value in gemmology, geology, paleontology and other disciplines. Previous studies on amber mainly focused on gemmological and spectral characteristics. In terms of micro-morphology, only a few achievements were made in Baltic honey wax and Dominican amber. Amber from Myanmar, as one of the important sources of amber, has great exploration space.In this paper, the microstructure characteristics of amber from Myanmar were studied by using infrared spectra and scanning electron microscope. Data of the amber from Myanmar has been calculated and analyzed, and the relationship of the microscopic characteristics, the quality and the density of beeswax were summarized. The formation reason of the structure of root amber from Myanmar and the formation mechanism of rubbery looks of brown amber from Myanmar were deduced. The results showed that root amber has a spongy and fibrous basis that contains gas bubbles with anomalous elliptical shape. The structure of root amber from Myanmar can be divided into two categories: Tight and loose.In addition, tight root amber contains uniformly distributed curved tubes ranging from 10 to 30 μm diameters, along which bubbles were gathered; While the size of bubbles in loose rough root amber was different, and the diameter of small bubbles was 1 to 2 μm, and the diameter of big bubbles was up to 11 μm. The conclusions can be drawn from the experimental results: (1) The proportion of bubble area and the uniformity of bubble distribution are positively correlated with the dense structure of root amber, that is, the larger the bubble area ratio, the smaller the bubble diameter, the more uniform the distribution, the denser the root Perot structure, and vice versa; (2) According to the shape, size and distribution characteristics of bubbles, the bubble in root amber of Myanmar can be inferred to be the self-contained volatile components of terpenes; (3) It can be speculated that the formation of bubbles in root amber is related to the volatile components such as terpenes and succinic acid carried by the resin itself, while the formation of empty tubes has two inferences. One is suspected to be the escape channel of volatile components. An alternative explanation is that the tubes are small cracks formed during the evolution of the amber; (4) It is first discovered that the typical crimson punctate inclusions of amber from Myanmar, and the scaly structure of such inclusions is significantly different from the ambient amber’s laminated structure,which can be inferred that the typical inclusions are probably related to some specific substances of the ingredients, especially the volatile substances. The reason why the crimson punctate inclusions can form a flow-like pattern has something to do with the directional escape of volatile compositions.
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Keywords:
- root amber /
- bubble /
- tube /
- red punctiform inclusion /
- SEM
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[1] 王徽枢.河南西峡琥珀的矿物学特征[J].矿物学报, 1989, 9(4):338-343. [2] 王雅玫,杨明星,牛盼.不同产地琥珀有机元素组成及变化规律研究[J].宝石和宝石学杂志,2014,16(2):10-15. [3] 谢祖宏,唐雪莲,李剑,等.缅甸琥珀不同品种的红外光谱特征[J].超硬材料工程,2013(5):52-56. [4] 王雅玫, 王芊莹, 聂淑芳.蜜蜡中气泡特征与品质的关系[J].宝石和宝石学杂志, 2016, 18(5):20-27. [5] 梁慧芳.缅甸琥珀组成元素测定以及光谱分析[D].北京:中国地质大学,2015. [6] 王妍,施光海,师伟,等.三大产地(波罗的海、多米尼加和缅甸)琥珀红外光谱鉴别特征[J].光谱学与光谱分析,2015, 35(8):2 164 -2 169.
[7] 张新言, 李荣玉.扫描电镜的原理及TFT-LCD生产中的应用[J].现代显示, 2010, 21(1):10-15. [8] 邢莹莹,亓利剑,麦义城, 等.不同产地琥珀FTIR和13C NMR谱学表征及意义[J].宝石和宝石学杂志,2015, 17(2):8-16. [9] 于丽芳,杨志军,周永章, 等.扫描电镜和环境扫描电镜在地学领域的应用综述[J].中山大学研究生学刊,2008(1):54-60. [10] Shi G, Grimaldi D A, Harlow G E. Age constraint on Burmese amber based on U-Pb dating of zircons[J].Cretaceous Research, 2012(37):155-163.
[11] Matuszawska A, Johna.Some possibilities of thin layer chromatographic analysis of the molecular phase of Baltic amber and other natural resins[J].Act A Chromatographica, 2004, 14(14):82-91.
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