The Gemmological Characteristics of a New Kind of Imitation of Turquoise
LI Shu1, DI Jing-ru1*, WANG Xiao-juan2, CAO Bai-hui1
1. Gemmological Institute, China University of Geosciences, Wuhan 430074, China 2. Henan Institute of Products Quality Inspection, Zhengzhou 450004, China
Abstract：A new kind of imitation of turquoise named “Violet” and “White buffalo” which is a type of associated mineral of turquoise have appeared on the market recently and are becoming increasingly popular. Conventional instruments, X-ray fluorescence spectrometer, Infrared spectrometer, X-ray powder diffraction, Scanning electronic microscope, UV-Vis have been employed to discuss the gemmological characteristics of this kind of imitation of turquoise in this paper, to study their chemical composition, mineral composition, microstructure, spectral characteristics and color emerging mechanism. The X-ray fluorescence spectrum shows that the chemical composition of the sample is complicated. The basic elements of different-colour samples are basically identical which contains of Ca, Al, P, Cu, Si, K, Fe, Ba. It can be deduced from the intensity of infrared absorption bend that the major anion group of this kind of imitation of tuequoise is PO3-4. The analysis for X-ray powder diffraction data indicated that the major mineral of the sample is crandallite and woodhouseite. Meanwhile, the scanning electron microscopy showed that the structure of the dense sample is determined by numerous of scaly, leaf-shaped and irregular granular aggregates. With the study of absorption spectrum, the conclusion is drawn that Fe3+ electronic transitions are the main factor for coloring of the sample and color varies with the content of Fe3+.
李 舒1，狄敬如1*，王笑娟2，曹百慧1 . 一种新型绿松石仿制品的谱学特征研究 [J]. 光谱学与光谱分析, 2016, 36(09): 2978-2983.
LI Shu1, DI Jing-ru1*, WANG Xiao-juan2, CAO Bai-hui1 . The Gemmological Characteristics of a New Kind of Imitation of Turquoise . SPECTROSCOPY AND SPECTRAL ANALYSIS, 2016, 36(09): 2978-2983.
[1] WANG Ping, DI Jing-ru, CHEN Si-si(汪 萍，狄敬如，陈偲偲). 绿松石加工工艺浅析. Collected Papers of Jewelry Academic Meeting of China University of Geosciences(中国地质大学(武汉)珠宝学院2012国际珠宝学术年会论文集)，2012. 109. [2] CHEN Quan-li, QI Li-jian, ZHANG Yan(陈全莉，亓利剑，张 琰). Journal of Gems & Gemmology(宝石和宝石学杂志)，2006, 8(1)：9. [3] HE Xu, CHEN Lin, LI Qing-hui, et al(何 煦，陈 林，李青会，等). Rock and Mineral Analysis(岩矿测试)，2011, 30(6): 709. [4] CHEN Quan-li, QI Li-jian(陈全莉，亓利剑). Rocks and Minerals(矿物岩石)，2007, 27(1): 30. [5] SHI Zhen-rong(石振荣). Geological of Jiangsu(江苏地质), 2008, 32(2): 109. [6] SHI Zhen-rong, CAI Ke-qin, GONG Ming-quan(石振荣, 蔡客勤, 龚明权). Geological of Northwest(西北地质), 2008, 41(2). [7] GAO Jie(高 洁). Superhard Material Engineering(超硬材料工程)，2008, 2(1)：58. [8] LUAN Li-jun, HAN Zhao-xin, WANG Chao-you, et al(栾丽君，韩照信，王朝友，等). Geological of Northwest(西北地质)，2004(3). [9] GUO Jing, XU Zhi(郭 倩，徐 志). Rocks and Minerals(岩石矿物学杂志)，2014, 2: 136.
