一种紫色蛋白石的宝石学特征  

Gemological Characteristics of a Type of Purple Opal

作　　者：范春丽[1] 程佑法[1] 郑秋菊[1] 王岳[1] 孙冰[1] 

机构地区：[1]国家黄金钻石制品质量监督检验中心,济南250014

出　　处：《超硬材料工程》2016年第1期53-57,共5页Superhard Material Engineering

摘　　要：针对市场上新出现的一种宝玉石品种,采用常规珠宝鉴定仪器及红外光谱仪、扫描电镜能谱仪、X射线衍射仪等大型分析仪器对样品的化学成分及矿物组成进行了分析。结果表明,样品的主要化学成分为SiO_2,含少量的CaF2。矿物组成主要为蛋白石,次要矿物为石英和萤石。根据国家标准应定名为蛋白石。样品主要宝石学鉴定特征为:外观深浅不同的紫色;玻璃光泽;微透明至不透明;密度通常在2.15~2.25g/cm^3,个别样品达到2.43g/cm^3;折射率为1.43~1.45,部分区域达到1.50;多数区域硬度较大,钢刀无法刻动,但局部紫色区域可刻动;紫外荧光下呈现为惰性。样品虽然在外观上与查罗石相似,但常规检测手段即可区分,如折射率、密度等。The chemical components and mineral composition of the sample of a new type of gemstone in the market have been analyzed by large analyzing instruments such as conventional jewelry appraisal instrument,infrared spectrometer,scanning electron microscopy（SEM）spectrometer and X-ray diffractometer,etc.The result shows that the chemical component is SiO_2 with minor CaF_2.The main mineral component is opal and the secondary minerals are quartz and fluorite.According to the existing national standard,it should be named as opal.The main gemological characteristics of the sample are as follows：different shades of purple in appearance;vitreous luster;subtranslucent to opaque;ageneral density of 2.15~2.25g/cm·3,with some individual sample up to 2.43g/cm^3;refractive index is 1.43~1.45 with some up to 1.50;the hardness is high for most parts and it can not be scratched by steel knife while some part of the purple areas can be scratched;it shows an inert nature under ultraviolet fluorescence.The sample is similar to charoite in appearance,but it can be distinguished by conventional testing method,such as the test of refractive index and density,etc.

关 键 词：蛋白石 萤石 宝石学特征 鉴别 

分 类 号：TS933.21[轻工技术与工程]