Nd-doped strontium lanthanum aluminate crystals, Nd:ASL (Sr1-xNdyLax-yMgxAl12-xO19), with an extended composition parameter x (0.05 and 0.5) have been grown by the Czochralski pulling technique. Structural and compositional properties of the as-grown crystals have been studied using X-ray diffraction, chemical microanalysis and optical spectroscopy. The results show that high crystalline perfection and large size crystals of both compositions can be grown. Low-temperature optical absorption spectra of crystals with compositions corresponding to x = 0.5 and 0.05 reveal that such crystals predominantly contain either C-1- or C-2-type Nd3+-centers, respectively. The possibility to thus differentiate between the two types of the dopant structural centers is of utmost importance for laser applications. (c) 2005 Elsevier B.V. All rights reserved.