The carbothermal reduction and nitridation of alkoxide-derived CaOSiO 2Al 2O 3 or Y 2O 3SiO 2Al 2O 3 mixtures was studied at 1200–1450°C. In the CaOSiO 2Al 2O 3 system, the formation of α-sialon was accelerated at 1450°C by the presence of a calcium-containing liquid phase. Additional heating at 1550°C for 1 h formed single-phase α-sialon powder. In the Y 2O 3SiO 2Al 2O 3 system, a multi-phase powder was prepared at 1300–1450°C. The formation of α-sialon powder with a small amount of SiC was possible by heating at 1450°C for 16 h and subsequent heating at 1600°C for 1 h.