RADIATION MEASUREMENTS

Rose quartz is an interesting mineral with numerous impurities that have been studied by scanning electron microscopy (SEM), X-ray fluorescence (XRF), X-ray diffraction (XRD), cathodoluminescence (CL), ion beam luminescence (IBL), radioluminescence (RL), thermoluminescence (TL) and optical absorption (OA). After HF etching, rose quartz from Oliva de Plasencia (Caceres, Spain) shows under SEM the presence of other silicate phases such as dumortierite [Al6.5-7(BO3)(SiO4)(3)(O, OH)(3)]. The OA spectrum of rose quartz suggests that these inclusions are the cause of coloration of rose quartz. The luminescence (CL, IBL, RL, TL) spectra behavior, at both room temperature and lower, confirms that the similar to 340 nm emission could be associated with Si-O strain structures, including non-bridging oxygen or silicon vacancy-hole centers; the observed similar to 400 nm emission could be associated with recombination of a hole trapped adjacent to a substitutional, charge-compensated aluminum alkali ion center; the similar to 500 nm emission could be associated with substitutional Al3+ and the similar to 700 nm peak could be associated with Fe3+ point defects in Si4+ sites. These results suggest that, while defect properties of rose quartz are not greatly dissimilar to those of purer forms of quartz and silica, further research seems necessary to determine criteria for the evolution of the newly-formed self-organized microstructures in the rose quartz lattice under irradiation. (C) 2007 Elsevier Ltd. All rights reserved