一颗辐照处理绿色Ⅱa型钻石的鉴定特征探讨  

Discussion on the Identification of an Irradiated Green type Ila Diamond

作　　者：朱文芳 祝晓霞[1] 赵鑫宇 叶宏[1] ZHU Wenfang;ZHU Xiaoxia;ZHAO Xinyu;YE Hong(National Gemstone Testing Center,ShenZhen 518020)

机构地区：[1]国家珠宝玉石质量监督检验中心深圳实验室,广东深圳518020

出　　处：《中国宝玉石》2020年第3期19-22,29,共5页China Gems & Jades

摘　　要：平均每一万颗钻石中才有一颗彩色钻石,而在彩色钻石中绿色钻石非常稀少,颜色能够达到艳彩级别的更是十分罕见。绿色钻石的成因主要有四类,其中最为常见的是辐照,并且该种成因致色的钻石的红外类型包括Ia型和Ⅱa型,但在实际检测中,天然辐照Ⅱa型钻石极为罕见。在NGTC深圳实验室发现Ⅱa型绿色钻石样品,这引起了检测人员的注意,经过检测,判定其为辐照处理钻石。通过测试样品的红外吸收光谱、紫外—可见近红外吸收光谱和光致发光光谱等特征,发现样品在741nm处呈现出较强的吸收,并且伴随着红区的一段宽吸收;在近红外光谱上可见9280cm-1的强吸收峰;在光致发光光谱上可见3H发光峰(503.4nm),并伴随着540.7nm发光峰。There is only one in 10,000 diamonds with a fancy color. Among the colored diamonds, green diamonds are rare and those graded fancy vivid green are extremely rare. There are four main causes of green diamonds, the most common of which are irradiation, and the infrared types of this kind of color-causing diamonds include type Ia and type IIa. However, in actual detection, naturally irradiated type IIa diamonds are extremely rare. A type IIa green diamond sample was found in the NGTC Shenzhen laboratory, which also aroused attention of gemologists. It was determined to be irradiated diamond after all the tests. Through testing the samples’ infrared absorption spectrum, ultraviolet-visible absorption spectrum and photoluminescence spectrum and other characteristics, it was found that the sample showed strong absorption at 741 nm and was accompanied by a wide absorption in the red region;and strong infra spectrum absorption peak at 9280 cm-1, 3 H emission peak(503.4 nm) can be seen in the photoluminescence spectrum, accompanied by 540.7 nm emission peak.

关 键 词：绿色钻石 辐照处理 GR1中心 3H中心 540.7nm 

分 类 号：P575.4[天文地球—矿物学]