Microdiamonds from the Saxonian Erzgebirge, Germany; in situ micro-Raman characterisation

The identity of diamond inclusions in quartz-muscovite gneisses near the Saidenbach reservoir, Saxonian Erzgebirge, was confirmed by laser-Raman micro-spectroscopy, and reinforced by the graphitization of the diamond inclusions by irradiation with a high-energy laser beam. These diamonds are mostly idiomorphic and < or = 30 mu m in size; they occur mostly in garnet but have also been found in zircon and kyanite. The microdiamond inclusions indicate ultra-high-P metamorphism of the host rocks.