翡翠B货的拉曼光谱鉴别

与传统宝石鉴定相比 ,拉曼光谱在漂白或注胶翡翠 (B货翡翠 )的鉴别中是一种快速、无损、微区分析方法 ,特别对于宝石中的包体和填充物尤其有效1 ] 。翡翠中经常充填各种油、蜡、胶 (如石蜡、石蜡油、AB胶、环氧树脂等 )来增强其透明度2 ] ,由于它们化学成分、化学结构的不同 ,在拉曼光谱中显示不同的峰位特征。环氧树脂的特征峰主要属于苯环的 :1 60 9和 1 1 1 6cm- 1 两个C—C伸缩振动 ,3 0 69cm- 1 C—H的伸缩振动以及 1 1 89cm- 1 C—H的面内弯曲振动 ,而用于翡翠抛光处理的石蜡不具有苯环的特征峰 ,据此可作为鉴别B货翡翠的依据。

Identification of B Jade by Raman Spectroscopy

Raman spectroscopy has been found to be a useful tool for identification of bleached and polymer-impregnated jadeites (so-called B jade). The major advantage of this system over classical methods of gem testing is the non-destructive identification of inclusions in gemstones and the determination of organic fracture filling in jade. Fissures in jadeites have been filled with oils and various resins to enhance their clarity, such as paraffin wax, paraffin oil, AB glue and epoxy resins. They show different peaks depending on their chemical composition. The characteristic spectrum ranges from 1 200-1 700 cm -1 to 2 800-3 100 cm -1. The spectra of resins show that they all have four strongest peaks related with phenyl: two C-C stretching modes at 1 116 and 1 609 cm -1, respectivey, one C-H stretching mode at 3 069 cm -1, and a in-plane C-H bending mode at 1 189 cm -1. In addition, other two -CH 2, -CH 3 stretching modes at 2 906 and 2 869 cm -1, respectively, are very similar to paraffin. Therefore, the peaks at 1 116, 1 609, 1 189 and 3 069 cm -1 are important in distinguishing resin from paraffin, and we can identify B jade depending on them.