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Several methods of manufacturing γ-aluminium oxynitride spinel (ALON) powder are discussed in this paper. In the carbothermal reduction process, ALON is an intermediate compound, and powders with a high ALON content may be produced in flowing nitrogen below 1650 °C if process parameters are carefully controlled. In addition, ALON may be produced when Al2O3/C mixtures are heated in a coke powder bed above 1650 °C. In the reaction sintering process, ALON is unlikely to form below 1600 °C in a flowing nitrogen atmosphere or in a coke powder bed, owing to the instability of ALON and the fact that the solid–solid reaction does not readily occur unless additives, e.g. MgO, MgAl2O4, are employed.