摘要
台湾花莲碧玉因其浓厚的颜色以及较细腻的结构和特殊光学效应受到广大消费者的喜爱。本文运用常规仪器、电子探针等测试手段研究台湾花莲碧玉宝石矿物学特征。通过科学全面系统的研究与前人资料对比可得,碧玉样品的颜色主要为淡绿-深绿色,颜色较为纯净,分布不均匀。内部可见黑色金属矿物杂质。具油脂-丝绢光泽,微透明-不透明,折射率为1.61,相对密度2.96~3.02 g/cm^3,硬度为6~7。碧玉的主要组成矿物为透闪石或者阳起石,次要矿物包括铬铁矿、铬钙铝榴石、透绿泥石。电子探针结果显示,碧玉样品的主要元素成分为MgO、SiO_2、CaO,以及少量的FeO和微量的Cr_2O_3、MnO、K_2O、Na_2O、Al_2O_3、TiO_2。根据样品数据的对比可以推测,碧玉颜色的深度与FeO的含量呈正比,当碧玉含有铬钙铝榴石包体时,碧玉颜色更鲜艳。
With its strong colors,delicate structure and special optical effects,the green Hualian nephrite of Taiwan is very popular among consumers.This paper deals with the gemological and mineralogical characteristics of green nephrite on the basis of basic test data and mineral compositions.Scientific,comprehensive and systematic research has a great significance for improving the scientific value and visibility of Hualian nephrite from Taiwan.The color of green nephrite ranges from light green to dark green,being relatively pure but distributed unevenly.Black metal mineral inclusions can be recognized,which have greasy-silky luster and are translucent to opaque.The green nephrite has refractive index of 1.61,relative densities from 2.96 to 3.02 g/cm3,and hardnesses from 6 to 7,and mainly consists of tremolite or actinolite,with minor grossular,chromite and chlorite.Electron microprobe analysis shows that the composition of green nephrite is characterized by relatively high values of MgO,SiO_2,CaO,comparatively low FeO,and minor amounts of Cr_2O_3,MnO,K_2O,Na_2O,Al_2O_3,TiO_2.The color of green nephrite has a positive correlation with the content of FeO.In addition,when the nephrite contains grossular,its color will become more bright.
出处
《岩石矿物学杂志》
CAS
CSCD
北大核心
2014年第S2期35-40,共6页
Acta Petrologica et Mineralogica
关键词
碧玉
花莲
宝石学特征
化学成分
nephrite
Hualian
gemological characteristics
chemical composition
