Flame‐excited luminescence (candoluminescence) has been measured for transition‐ion‐activated phosphors , , and . Willemite and the Cr‐activated phosphors exhibit candoluminescent spectra similar to emission spectra obtained by other excitations. The emission spectra of is profoundly different. Certain other common phosphors , , Pb, and do not luminesce under flame excitation. All emitting phosphors require a temperature of several hundred degrees centrigrade for most efficient emission.