Abstract The doping of feldspars by Ga, In and Tl leads to the appearance of intense specific emission bands. Their spectra and decay kinetics were measured at 4–290 K in 2–8 eV spectral range. The lowest excited state of the impurity centre proves to be related to the excited 3P state of corresponding ns 2 ion. This is the reason for the long decay times (~ 10 −3 − 10 −4 s at 4 K), sharply depending on temperature. The higher excited states of the centres apparently are the activator-oxygen hybrid states. Monovalent ns 2 ions possibly substitute Na + or K +ions in the K(Na)AlSi 3O 8 lattice. As follows from the lattice structure of alkali feldspars, they can have several different types of nearest neighbours.