马达加斯加含定向包裹体磷灰石的宝石矿物学特征
Gemmological and Mineralogical Characteristics of Apatite from Madagascar with Directional Inclusions
李星彤 1徐畅 2郑金宇 2沈洪涛 3沈锡田 1张倩1
作者信息
- 1. 中国地质大学(武汉)珠宝学院,湖北武汉 430074
- 2. 中国地质大学(武汉)地球科学学院,湖北武汉 430074
- 3. 中国地质大学(武汉)地质过程与矿产资源国家重点实验室,湖北武汉 430074
- 折叠
摘要
含定向包裹体的晶体经定向切磨后,可呈现包括星光效应与猫眼效应在内的特殊光学效应.因其美丽的外观,这种宝石在市场上受到消费者的喜爱.磷灰石内部常见丰富的定向包裹体,切磨后可以呈现猫眼效应.猫眼磷灰石很常见,在一些非洲与亚洲国家均有产出.但与刚玉、石榴石与金绿宝石等常见宝石相比,关于磷灰石内部定向包裹体的组分、成因的系统性研究较少.因此,本文通过显微镜、拉曼光谱仪、扫描电子显微镜、X射线能谱仪、磁性测试对一种产自马达加斯加的含定向排列包裹体的磷灰石样品进行了较为系统的测试分析.显微观察表明,磷灰石样品内部含有大量具金属光泽的针状包裹体,平行主晶c轴生长,切磨成弧面型宝石后可产生猫眼效应.EDS结果表明,包裹体出露区域富含Fe与O元素,指示包裹体为一种铁氧化物.拉曼光谱显示包裹体具有位于662 cm-1处的弱拉曼峰,可归属为磁铁矿的A1g振动峰.磁滞回线测试进一步表明包裹体为亚铁磁性物质,表明针状包裹体的成分为磁铁矿.磷灰石内部的定向磁铁矿包裹体并不常见,该研究结果对磷灰石内含物研究领域提供了新的见解.
Abstract
In this study,the apatites containing directional arrangement inclusions from Mad-agascar were investigated using microscope,Raman spectroscopy,scanning electron micro-scope(SEM),X-ray energy dispersive spectroscopy(EDS),and magnetic test.Microscopic observation results show that there are abundant needle-like inclusions with metallic luster,which are parallel to c-axis of the apatite crystal.These inclusions could produce the cat's eye effect of apatite under the light.EDS results reveal that Fe and O elements are rich in the exposed region of inclusion,suggesting that it is a type of iron oxide.Raman spectroscopy displays a weak peak at 662 cm-1,which can be attributed to the A1g vibration mode of mag-netite.The hysteresis loop test confirms that the inclusions are ferromagnetic substances,indicating that the needle-like inclusions are magnetite.
关键词
磷灰石/猫眼效应/定向包裹体/磁滞回线/磁铁矿Key words
apatite/cat eye's effect/directional arrangement inclusion/hysteresis loop/magnetite引用本文复制引用
出版年
2024
NETL
NSTL
万方数据