北京昌平地区京粉翠的宝石学特征及其致色原因

京粉翠具有艳丽高雅的粉桃红色、玫瑰粉红色等喜人的色泽,但是到目前为止对于其致色原因尚不清楚.针对北京市昌平区的4种不同颜色的京粉翠,进行了宝石学常规参数的测定实验,以及对特征矿物进行了电子探针分析.通过宝石学特征发现,京粉翠随着颜色的增加,其折射率略有增加,其密度随着颜色的加深而增加.通过观察不同颜色的京粉翠在偏光显微镜下的特征,发现京粉翠的主要矿物组成为：蔷薇辉石、石英和长石等.通过不同颜色的矿物电子探针的分析,得出京粉翠的致色成因主要由其中Mn元素含量决定,Fe的含量也起一定的影响作用.

The Gemology Characteristics and Color-causing of Peking Rhodonite in Changping Disctirct,Beijing

Peking Rhodonite has bright pink, rose pink and so gratifyi are unclear. The research on four different colors of Peking Rhodonite ng color, but so far the reasons for its color in Changping District of Beijing was carried out by means of field survey and gemological characteristics＇ identification and microscopic study as well as the E- lectron Probe Micro Analysis （EPMA）. The refractive index increases slightly with the deepening of the color, while the density increases too. Peking Rhodonite is mostly composed of rhodonite, quartz and feldspar. Its color is caused mainly by the amount of Mn, while Fe also has an influence on its color.