THERMOLUMINESCENT SPECTRUM CHANGES OF NATURAL QUARTZES DEPENDENT ON ANNEALING TREATMENT AND ALUMINUM-CONTENTS

Both of fused and annealed natural quartzes were spectroscopically analyzed by using the IPDA (intensified photodiode array) on-line spectrometric system for measuring 3-dimensional thermoluminescence (TL) glow-curves. A remarkable change of TL property from red to blue occurred after the transformation to fused quartz glass. The TL properties were also searched after thermally annealing treatment for 100 h at 1100 degrees C Apparently different changes of TL-colorations were found to occur even within a Z-cut slice from a single quartz crystal; the original blue-TL quartz segments with higher Al-contents than about 100 ppm are readily changeable into red-TL color after the thermal annealing, presumably in cooperation with other impurities. Accordingly, the existence of Al-0-Al and/or Al-0-Si bond in natural quartz has been tentatively considered to play an important role of red-TL color at high temperature.