A hybrid gel synthesis is described which produces crystalline lanthanum hexaluminate at 1200 degrees C without the intermediate appearance of LaAlO3. XRD in conjunction with Al-27 and La-139 MAS NMR indicates that until the exothermic appearance of gamma-alumina at about 900 degrees C, the gel remains amorphous and contains Al in three types of site, one of which is characterised by an NMR resonance at 36 ppm. By 1200 degrees C, the La ions have moved into the mirror planes between the gamma-alumina blocks and the crystallinity of the LaAl11O18 which forms in an exothermic event at about this temperature continues to improve with further heating to 1350 degrees C.