By using routine gemological testing, thin section observation under microscope, Fourier Transform Infrared (FTIR) Spectrometric analysis and the chemical analysis method, a systematic study of nephrite jade from Huanren has been investigated for minerals, chemical compositions and gemological characteristics. The results indicate a refraction index of 1. 60, specific density of 3. 08 and Mohs hardness of about 6. 5. Thin section observation by polarizing microscope show that the main mineral composition is of epidote and hornblende and the impurity minerals are diopside, apatite, carbonate minerals and serpentine among others. The main textures of the jade are inequigranular blastic, foliated pilotaxitic and metasomatic. The specific texture characteristics of the nephrite are responsible for its poor transparency, uneven color distribution, and the inclusions of black spots and green agglomerate. The features of the infrared spectra are very similar to those of standard reference tremolite which indicate that the jade is indeed nephrite. The chemical analysis results were similar to Hetian's jade and Xiuyan's nephrite jade. The impurities of hornblende ( biotitization) affected the quality of the jade.%利用常规检测及薄片观察、红外光谱、化学分析法,对产自辽宁桓仁的一种灰白色玉石的矿物成分、化学成分及宝石学性质进行了较为系统的研究.测得其折射率为1.60,相对密度为3.08,摩氏硬度为6.5±.偏光显微镜下显示玉石的主要组成矿物为透闪石及普通角闪石,杂质矿物为透辉石、磷灰石、碳酸盐矿物、蛇纹石等,呈不等粒变晶结构、叶片状变晶结构及交代结构.玉石的组构特征导致其透明度较差,颜色不均匀,具黑色斑点及绿色团块状包体.红外光谱特征与标准的透闪石特征非常相近,证明该玉石为透闪石玉(软玉),其化学分析结果与和田玉及岫岩软玉结果相近.普通角闪石的存在(已黑云母化)一定程度影响了玉石的品质.
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