Fullerenes are not automatic candidates for luminescence analyses due to their highly absorptive nature. Consequently, very few luminescence experiments have been performed on fullerenes. This paper focuses on the luminescence properties of commercially available C-60 when bombarded by electrons (cathodoluminescence) and, to a lesser extent, x-rays (radio-thermoluminescence) between 20 and 270 K. Wavelength resolved luminescence signals have been recorded as a function of temperature. CL experiments reveal pronounced anomalies that truncate the emission spectrum between 155 and 170 K. Other less pronounced anomalous features are detected at 70 and 245 K. These dramatic changes in the luminescence spectra are cautiously interpreted to be manifestations of phase transitions and support the view that cathodoluminescence (CL) can be used to monitor for phase transitions in fullerenes. The luminescence signals offer information on the mechanisms of the relaxation processes, including changes in charge trapping energies and emission spectra.