俄罗斯高温高压处理钻石特征

采用显微观察、红外光谱、可见吸收光谱和低温光致发光谱等分析方法,对9颗俄罗斯高温高压处理钻石样品进行了研究。结果表明,该类钻石样品的内部多见石墨化现象,尤以彩色钻石样品更明显;金黄色、紫红色、黄绿色样品为ⅠaAB型,浅黄色样品为ⅠaB型,近无色样品为Ⅱa型;样品的可见吸收光谱因颜色不同而差异显著,其中金黄色样品可见475 nm处的吸收宽带,紫红色样品可见638,614,595 nm处的吸收峰,黄绿色和浅黄色样品可见415,475,503 nm处的吸收峰,近无色样品则为较光滑的平直曲线。此外,该类样品在低温光致发光谱中可见575 nm与637 nm处强发光峰。这些特征为探讨该类钻石的晶格缺陷与呈色机理提供了一定的科学依据。

Characteristics of HTHP-Treated Diamonds from Russia

In the paper,the nine HTHP-treated diamond samples from Russia are test by using the micro-examination,FTIR,visible absorption spectrum,low-temperature photoluminescence spectrum and some other methods.The results show that the diamond samples reveal the obvious graphitization,especially the fancy colour diamond samples.The golden yellow,purplish-red,yellowish-green samples are Ⅰ aAB-type;light yellow sample is Ⅰ aB-type and the near colourless samples are Ⅱ a-type.The visible absorption spectra of the samples are very different by the colours.The golden yellow sample reveals the wide absorption band at 475 nm;purplish-red samples reveal the absorption peaks at 638,614,595 nm;the yellowish-green samples reveal the absorption peaks at 415,503 nm and the absorption band at 475 nm;the near colourless samples in the visible region are almost smooth.Besides,the strong luminescent peaks of the samples at 575 nm and 637 nm are observed in the low-temperature(77 K) PL spectra.These characteristics above could provide the foundations for the study on the defects in the crystal lattice and the colouring mechanism of the HTHP-treated diamond.