一种斜绿泥石质仿田黄  

Clinochlorite:A New Type of Tian Huang Imitation

作　　者：潘小青[1] 沈忠悦[1] 张志亮[1] 俞丹燕[2] 

机构地区：[1]浙江大学地球科学系,浙江杭州310027 [2]浙江省黄金珠宝饰品质量检验中心,浙江杭州310013

出　　处：《宝石和宝石学杂志》2011年第3期27-31,共5页Journal of Gems & Gemmology

摘　　要：田黄是一种产于福建寿山、以地开石或珍珠陶石为主要矿物组成的玉石,其具有＂形＂＂皮＂＂格＂＂纹＂特征。由于田黄的价格昂贵,市场上常有田黄仿制品出现。主要介绍一种斜绿泥石质田黄仿制品材料,该斜绿泥石质仿田黄为黄色至褐黄色,玻璃光泽,半透明,具有似＂萝卜丝纹＂与＂红筋＂,外貌上与田黄十分形似,较易混淆,但斜绿泥石质仿田黄的透明度较田黄的好;该斜绿泥石质仿田黄的实测折射率为1.585,相对密度为2.81,二者均较田黄的高;X射线粉末衍射分析,斜绿泥石以14.39,7.14,4.74,3.55处的衍射峰为特征,而田黄则没有14附近的衍射峰;红外光谱的结果显示,虽然斜绿泥石质仿田黄和田黄均在3 700~3 400 cm-1范围内具有羟基吸收,但前者显示宽吸收基础上叠加了3 679,3 671,3 651和3 629 cm-1处4个极弱的肩形峰,而后者却有3 700,3 645,3 625 cm-1处的尖锐的强吸收峰。运用X射线粉末衍射分析或红外光谱、折射率和相对密度等测试方法可将其区别开。Tian Huang,which has its own features in shape,skin and grain,is a kind of jade produced at Shoushan Village in Fujian Province.Its main mineral component is dickite or nacrite.However,there are lots of imitations in the market due to the high price of Tian Huang.In this paper,a new type of Tian Huang imitation which is mainly composed of clinochlorite is identified.The Tian Huang imitation is yellow to brownish yellow in colour,and translucent with glassy luster.What＇s more,＂radish grain＂ and ＂red grille＂ can be found in the Tian Huang imitation.As a result,it is difficult to distinguish the imitation from Tian Huang by only judging the exterior appearance.However,the Tian Huang imitation is more transparent than Tian Huang.The measured refractive index is 1.585 and the specific gravity is 2.81 for the Tian Huang imitation,which are higher than that of Tian Huang.By X-ray powder diffraction analysis,clinochlorite is characterized by the diffraction peaks at 14.39,7.14,4.74,3.55  while Tian Huang is lack of 14 .Both of the Tian Huang imitation and Tian Huang show their hydroxyl absorptions between 3 7003 400 cm-1 in the infrared spectra.It is worth emphasizing the difference that the Tian Huang imitation has faint shoulder-shaped absorptions at 3 679,3 671,3 651 and 3 629 cm-1 over a broad absorption,while Tian Huang has sharp absorptions at 3 700,3 645,3 625 cm-1.Hence,it is not difficult to identify Tian Huang from clinochlorite by means of X-ray powder diffraction,infrared spectrum,refractive index and specific gravity measurement.

关 键 词：田黄 斜绿泥石 仿制品 X射线粉末衍射 红外光谱 

分 类 号：TS93[轻工技术与工程]