a working document by global witness. 10 may 2000 This working report has been produced by Global Witness. Partial funding for this report was kindly received from the UN department of the UK Foreign and Commenwealth Office (FCO), without which this report would not have been possible. The views expressed within are solely those of Global Witness. There are many individuals, companies and count...

In this article, the spectroscopic methods used to assess gem-quality diamonds are reviewed. From such measurements it is possible to determine, in the majority of cases, whether the colour of a stone is natural, or has been changed by some form of treatment—either HPHT processing, radiation damage and annealing, or a combination of both methods. Methods used to identify synthetic diamonds are ...

This article provides information on modern developments in the direction of directed impact cutting surface a diamond-abrasive tool and its contact zone machining processes. For most part, such processing is faced with issues influence diamond tools, including ruling mechanical electrophysical, taking into account defectiveness diamonds that undergo processing, diamonds, thermal modification d...

Queries that constrain multiple dimensions simultaneously are difficult to express, in both Structured Query Language (SQL) and multidimensional languages. Moreover, they can be inefficient. We introduce the diamond cube operator to facilitate the expression and computation of one such important class of multidimensional query, and we define the resulting cube to be a diamond. The diamond cube ...

Marilyn Monroe knew that "diamonds are a girl's best friend" but, in the meantime, many chemists have realized that they are also extremely attractive objects in contemporary chemistry. The chemist's diamonds are usually quite small (herein: nanometer-sized "diamondoids") and as a result of their unique structure are unusual chemical building blocks. Since lower diamondoids (up to triamantane) ...

Since the original classification of diamonds based upon their absorption in the one-phonon region of the mid-infrared (IR) range was first introduced, a vast amount of research has been carried out in this field. The result today is that IR analysis has become the principle tool for classifying diamonds based upon the concentration and aggregation state of nitrogen, the most common impurity fo...

Long after worldwide acceptance of the GIA-established standard of UV-free, daylight-colour-balanced illumination for the correct colour grading of a diamond's “true body colour”, an examination of diamond trade and laboratory grading practices finds nearly everyone, including GIA, employing some type of fluorescent tube lighting. GIA taught that this lighting “causes fluorescent diamonds to be...