【作者】 李敬敬；

【导师】 王礼胜；

【作者基本信息】 石家庄经济学院 ， 矿产普查与勘探， 2007， 硕士

【摘要】 针对目前粉—紫色系列翡翠系统深入的研究不多,甚至相关的认识不尽一致的现状,本文主要从粉—紫色系列翡翠的物理性质、结构构造、矿物组成及化学成分、矿物晶体结构、呈色机理、优化处理品的鉴定及质量评价要素等方面对其进行系统的宝石学研究。具体内容如下:常规宝石学测试结果:粉—紫色系列翡翠的摩氏硬度为6.5～7,比重为3.27～3.34,折射率在1.66左右,紫外灯下无荧光反映,紫区437nm吸收谱线易见,反射光下常有明显的“翠性”。通过偏光显微镜下薄片观察及阴极发光现象分析,翡翠的结构可分为静态重结晶作用形成的结构和交代作用形成的结构以及动力变质作用形成的结构。从一定意义上看,动力变质带属于不同性质的剪切带,根据剪切带类型将翡翠的结构分为脆性剪切带中形成的角砾状结构、碎裂结构和脆—韧性剪切带中形成的碎斑结构以及韧性剪切带中的糜棱结构等。基质的含量及动态重结晶程度的不同可将糜棱结构细分糜棱岩化结构、初糜棱结构、糜棱结构及超糜棱结构。不同结构翡翠的种质有很大的差异。所研究样品中粉色翡翠多为条带状构造,紫色翡翠常有斑杂状构造。在某些特定条件下,块状构造、脉状构造等也可在粉—紫色系列翡翠中出现。在本文对所收集粉—紫色系列翡翠样品的矿物组成研究中,通过显微镜下观察及X射线粉晶衍射分析,发现该系列翡翠的组成矿物为单—的硬玉。电子探针测试及晶胞参数结果表明粉—紫色系列翡翠的化学成分较纯,微量元素的种类及含量都较少。粉色翡翠与相同样品中的白色翡翠在化学成分上具有继承性,结合其结构可知,白色部分是粉色翡翠在脆性作用下碎裂形成;紫色斑晶的化学成分较稳定,而淡绿色基质化学成分变化较大,并且通过薄片观察发现基质围绕紫色斑晶呈旋转构造,有时穿插或交代紫色斑晶,说明紫色斑晶早于淡绿色基质。电子探针分析及热处理改色试验结果表明,粉色翡翠为色心致色,紫色为微量元素Mn引起的颜色。粉—紫色系列翡翠的优化处理品的鉴定中,在传统鉴定方法的基础上重点介绍大型仪器在鉴定中的应用。从颜色、质地及体积三方面对粉—紫色系列翡翠进行质量评价。更多还原

【Abstract】 Systemic gemological researches on pink-purple series of feicui have been carried out in this text. Physical properties, rock structures and constructions, mineral constituents, chemical compositions of minerals, crystalline structures, and essential factors of quality appraisal have been studied. A comprehensive summary to gemological characteristics of the pink-purple series of feicui is meaningful for clarifying some fuzzy understanding, and filling some blanks in the research. The conclusions are as follows:Physical properties of pink-purple series of feicui are similar to which of white and pale-green feicui. Their densities are from 3.27 to 3.34, refractive indexes are about 1.66, hardnesses of Mohs are from 6.5 to7.Through microscope observation and analyses of cathodoluminescence maps, formimg processions of feicui can be divided into static recrystallization, dynamic metamorphism and metasomatosis. Structures forming from dynamic metamorphism include mylonite structure, porphyroclasts structure and the structure of fragmentation. Common types of rock construction include stripped construction of pink feicui and taxitic construction of purple feicui.The mineral constituents of the pink-purple series of feicui are pure, by jadeite primarily; Electron probe analyses indicate that chemical composition of pink-purple series of jadeites are close to the theoretical values.Electron microprobe analyses and high temperature oxidation - reduction reactions indicate that color center results in pink color of feicui, yet trace element Mn makes feicui be purple.In the identification of enhanced and treated pink-purple series of feicui, besides traditional gemological methods, applications of large-scale instruments are valuable. The essential factors of quality appraisal are color, texture and volume.更多还原