合成钻石饰品“Lightbox Jewelry”的宝石学特征

Gemmological Characteristic of Synthetic Diamond “Lightbox Jewelry”

国家珠宝玉石质量监督检验中心(NGTC)收集了无色、粉色、蓝色的合成钻石饰品品牌“Lightbox Jewelry”的样品,并进行了详细的测试工作,包括显微镜观察、发光图像观察、光谱学测试等。研究表明,Lightbox Jewelry饰品的主石为CVD合成钻石,红外光谱均显示为Ⅱa型;拉曼光致发光光谱均可测得596/597 nm发光线,指示样品均未经历过后期高压高温处理,部分可测得737 nm双线,粉色样品还可见明显的595、637、741 nm等特征吸收,推测其在合成后期可能经历了辐照退火处理;蓝色样品紫外-可见吸收光谱可见621 nm宽带、741 nm吸收峰,红外光谱可见9 287 cm^-1吸收峰,推测其经历了辐照处理。对无色配石进行了测试研究,发现绝大多数配石为高压高温合成钻石,另外混入了个别天然钻石。

“Lightbox Jewelry”synthetic diamond is the first brand product of synthetic diamond released in September 2018 by De Beers,which has several series of colours including colourless,pink and blue.The Lightbox Jewelry synthetic diamond jewelry samples have been collected and systematically investigated by using microscopic observation,DiamondView TM fluorescence imaging and spectroscopic techniques.The results show that the main stones of Lightbox Jewelry are CVD synthetic diamonds.The gemmological characteristics of the samples are as follows:IR spectra showed they were typeⅡa;596/597 nm doublet emissions appeared in all samples,737 nm doublet were present in some of the samples;The existence of 596/597 nm doublet emissions indicated that the samples had not undergone the post-growth HPHT treatment.In addition,for pink samples,absorptions at 595,637 nm and 741 nm were recorded.It was speculated that the pink samples have been received irradiation annealing treated.For blue samples,their UV-Vis absorption spectra showed a broad band at 621 nm and a absorption peak at 741 nm,and their IR spectra showed 9 287 cm-1 peak,speculating that the blue samples had undergone the treatment of irradiation.The melee-size colourless diamonds of Lightbox Jewelry were also tested and studied.It was also found that most of the melee-size diamonds are mainly HPHT synthetic diamonds mixed with a few natural diamonds.