多过程处理IIa型粉色钻石的鉴定特征  

Identification Characteristics of Type IIa Pink Diamonds Treated with Multiple Processing Techniques

作　　者：汪洋 宋中华 潘迪 陶震东 陆真平 程愉涵 WANG Yang;SONG Zhonghua;PAN Di;TAO Zhendong;LU Zhenping;CHENG Yuhan(Guangzhou Lab,National Gems and Jewelry Testing Co.,Ltd.,Guangzhou,Guangdong 511483,China;National Gems and Jewelry Testing Co.,Ltd.,Beijing 100013,China)

机构地区：[1]国家珠宝玉石首饰检验集团有限公司广州实验室,广东广州511483 [2]国家珠宝玉石首饰检验集团有限公司,北京100013

出　　处：《现代地质》2025年第1期231-238,共8页Geoscience

基　　金：国家自然科学基金项目(42073008);国家珠宝玉石质量监督检验中心科研基金项目(NGTC20220100)。

摘　　要：天然钻石可以通过高温高压处理产生孤氮、辐照产生空位,并经过退火过程促使孤氮和空位聚合产生NV色心,这种多过程处理可将钻石转变为粉色。处理原材料通常为Ia型钻石,色彩由N3缺陷及高浓度的NV色心共同致色,最终呈现深紫红至深红色。随着技术的进步,近年来市场上出现了以IIa型钻石为原材料的多过程处理粉色钻石。由于其氮含量极低,处理后的钻石通常展现出更为浓郁的粉色调,且与天然NV致色的钻石及引入NV致色的合成钻石相似。为全面了解此类IIa型处理粉色钻石的鉴定特征,本文选取了两件样品进行详细的宝石学特征测试及多种光谱分析。通过宝石显微镜观察,样品呈现出明显的石墨化现象。紫外-可见-近红外吸收光谱显示,处理钻石样品的颜色由GR1吸收、NV吸收及其发光共同形成。由于GR1和NV缺陷浓度的差异,两件处理钻石的色调略有不同,其中一件呈现橙粉色,另一件则呈现紫粉色。近红外吸收光谱观察到辐照相关的9287 cm^(-1)吸收带,而PL光谱则显示了辐照相关缺陷3H、GR1发光和595 nm吸收等特征。在DiamondView下,所观察到的典型“马赛克”状结构是区分此类多过程处理IIa型粉色钻石与合成粉色钻石的最直接特征。A multiple-treatment process was developed to produce orange-pink-red coloration into both natural and synthetic diamonds through the controlled introduction of NV centers,including HPHT annealing and subsequent irradiation and annealing.Most of these processed diamonds are Type Ia,coloured by the N3 center and high concentration of the NV center,result in deep purplish red to deep red diamonds.With the development of technology,there have been type IIa multiple-treatment pink diamonds on the market in recent years,which have lower nitrogen content and more vibrant pink hue compared to Type Ia diamonds.And the color of such processed diamonds is closer to untreated natural pink Type IIa diamonds coloured by NV centres,treated synthetic diamonds coloured by the introduction of NV centres.Two multiple-treated natural pink diamonds have been tested and analysed in detail to better understand their identification characteristics and to facilitate differentiation from other types of Type IIa pink diamonds.Graphitized fractures and crystal inclusions were visible under the microscope.UV-Vis-NIR spectra collected at liquid-nitrogen temperature showed strong GR1 and NV centers,the emissions of the NV centers were superimposed on the absorption spectrum.The different concentration of the NV and GR1 defects resulted in different hues of the two diamonds,one purplish pink and the other is orangy pink.In the near-infrared region,the dominant feature was strong absorption band at 9,287 cm^(-1),which has been reported to be related to irradiation treatment.Irradiation-related PL peaks 3H,GR1 and 595nm absorption were detected.The growth structure under DiamondView is still the main identification basis for natural and synthetic pink diamonds.

关 键 词：粉色钻石 NV色心 IIa型钻石 多过程处理 辐照退火处理 

分 类 号：P574.19[天文地球—矿物学] P575.4[天文地球—地质学] P585.1