Journal of the Korean Crystal Growth and Crystal Technology (한국결정성장학회지)

The Korea Association of Crystal Growth (한국결정성장학회)
권호 표지

A study on the HPHT-processed NOUV diamonds by means of their gemological and spectroscopic properties

  • Published : 2005.06.30
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Abstract

This study has been carried out with the eight HPHT processed NOUV diamonds - two yellow, two yellowish green, two green and two orangy yellow color stones. The gemological properties of these diamonds included a highly saturated body color, graphitized fractures around the girdles, tension cracks around crystalline inclusions, long-wave UV with medium yellowish green to a very strong yellowish green luminescence, and short-wave UV with faint yellowish green to a strong yellowish green luminescence. Distinctive features of spectroscopic properties include absorption peaks at 415 nm and 503 nm a strong absorption band at $460{\sim}480nm$ and a H2 center at 986nm. Infrared spectra showed an absorption peak at $1344cm^{-1}$ (C center), which is the characteristics related to single substitutional nitrogen.

Keywords

References

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