巴基斯坦祖母绿的红外光谱和包裹体特征研究  

Infrared spectra and inclusions of emeralds from Pakistan

作　　者：郭鸿舒 余晓艳[1] GUO Hong-shu;YU Xiao-yan(School of Gemology,China University of Geosciences,Beijing 100083,China)

机构地区：[1]中国地质大学珠宝学院

出　　处：《岩石矿物学杂志》2019年第5期724-732,共9页Acta Petrologica et Mineralogica

摘　　要：通过宝石显微镜、显微红外、电子探针和拉曼光谱等测试方法对巴基斯坦祖母绿的孔道水和包裹体进行了研究。红外光谱测试可知,巴基斯坦祖母绿中存在Ⅰ型和Ⅱ型水,且Ⅱ型水(5270、3600、1632 cm^-1)吸收强度远大于Ⅰ型水(1600 cm^-1)。流体包裹体以气液两相包裹体为主,常呈拉长状或"卡脖子"状形态,且定向排列,气相包裹体主要成分为CO2+N2+CH4的混合气体,液相主要为水溶液;矿物包裹体主要有菱镁矿、白云石、白云母、石英等。特征包裹体和红外光谱特征有助于鉴定巴基斯坦祖母绿的产地来源。In this paper,the inclusions and the structural water in the microchannel in emeralds from Pakistan were investigated by using optical microscopy,infrared microspectroscopy( FTIR),Raman spectroscopy and electron microprobe analyzer( EPMA). The emeralds from Pakistan contain type Ⅰ and type Ⅱ waters. The infrared spectra show that the intensity of water type Ⅱ( 5 270,3 600,1 632 cm^-1) is much stronger than water type Ⅰ( 1600 cm^-1). Most of the multiphasic inclusions in these emeralds are of biphasic elongated shape or are"neck-licking"inclusions,which consist of liquid( H2O) and gas,including carbon dioxide gas( CO2)+ nitrogen( N2)+methane( CH4). The main solid inclusions are magnesite,dolomite,muscovite and quartz. These inclusions and infrared spectra contribute to distinguishing Pakistani emeralds from emeralds of other origins.

关 键 词：祖母绿 红外光谱 拉曼光谱 包裹体 巴基斯坦 

分 类 号：P578.953[天文地球—矿物学] P575[天文地球—地质学]