Value addition in diamonds and other gemstones by nuclear radiation: the phobias and safety considerations

Abstract

Four Cs, namely colour, clarity, carat (weight) and cut, primarily determine the price of a gem. Neutron irradiation, gamma rays and electron beams can be used to enhance the colour and clarity of aquamarine, quartz, tourmaline, kunzite, topaz, pearls and, most importantly, diamonds. Imparting colour and clarity to these gems that are otherwise devoid of these attributes results in significant value addition. The enhanced gems may possess stable or unstable colours, depending on the nature of the colour centre produced. This paper reviews the processes of enhancement of topaz and diamonds with a special emphasis on neutron irradiation. In view of the radioactivity generated as a result of exposure to neutrons and the likelihood of undue exposure to radioactive gems, the safety aspects are discussed. From the commercial viewpoint, the aspect of detection of treated materials has been documented. A related technique, the process of enhancement of gems by gamma rays, has been described. The enhancement of gems by radiation (in synergy with heat) is a commercially viable technique and constitutes a peaceful application of nuclear technology. It has potential and future prospects in Gulf Cooperation Council (GCC) member states.