In previous work the thermoluminescence of golden sapphire (Al2O3containing Ni and Mg), which was &ggr; irradiated under liquid nitrogen, was compared with glow curves of fused borax seeded with Ni and Mg. The emission intensity obeyed, reasonably well, the expressionI=&agr;N0k′ exp−1/(dT/dt)t0tk′dT. In the present paper it is shown that light‐induced glow curves in &ggr;‐irradiated sapphire have the form of a second‐order decay process, namelyI=I0[b/ (b+t)]m. Gamma‐ray induced thermoluminescence in ruby shows dominant emission bands with maxima at about 150°K and 240°K. Light‐induced thermoluminescence in &ggr;‐ray damaged ruby shows an afterglow long after the crystal has reached room temperature.