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Characterization of pink diamonds of different origin: Natural (Argyle, non-Argyle), irradiated and annealed, treated with multi-process, coated and synthetic Branko Deljanin, Dusan Simic, Alexander Zaitsev, John Chapman, Inga Dobrinets, Annette Widemann, Nicholas Del Re, Tara Middleton, Elena Deljanin and Andrea De Stefano Purchase the full article here. One of the commercial challenges today in the gem industry is to quickly identify the origin of color in pink diamonds — natural, treated and synthetic by use of standard and advanced gemological instruments. An analytical technique that is used by many gem labs involves UV fluorescence. The principle factors in the technique are the excitation wavelengths and the emission spectra. No systematic study of fluorescence of pink natural diamonds, pink treated and pink synthetic diamonds has been undertaken. This study is mainly focused on using fluorescence techniques to characterize pink diamonds and to compile a reference library of emission spectra. Longwave (LW) and shortwave (SW) fluorescence of 365, 254 and 220 nm illumination were used in a custom built microscope with a fluorescence camera to record images and a spectrometer to record spectral data with which to establish a correlation with the cause of color. Other advanced instruments (CL imaging, UV–VIS–NIR, FTIR, PL spectroscopy and electrical conductance) were used to establish additional criteria for distinguishing natural, treated and synthetic pink diamonds and to find a correlation with the “EGL USA CIS (Cross-reference Identification System) fluorescence method”. Article Outline:
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Informative Articles Informative Articles To keep you abreast of new discoveries in gemstone research, synthetics and treatments, we have listed a selection of informative articles written by experts in their field.
Check this page regularly for updates. "European Gemological Laboratory Defines SI3" Adding the SI3 clarity grade to the grading system was the next logical step. 'The Scoop on synthetics' Can we ID them? Should we grade them? Do we need them? 'Cultured Confusion' Should a man-made diamond be called "synthetic", or "cultured" and who are the important players in this controversial addition to the diamond industry? "A Gemological Study of A Collection of Chameleon Diamonds" The rarity of chameleon diamonds and their interest for the connoisseur are due to their unusual ability to change color temporarily when heated to about 150C, or after prolonged storage in the dark. "Interpreting Diamond Morphology" - Part I A diamond's morphological features reflect conditions of diamond formation and represent a unique characteristic than can be used to identify details of the sources of diamonds. "Interpreting Diamond Morphology" - Part II Morphological features reflect conditions both during diamond formation and also after emplacement, especially where alluvials are concerned. |
