Abstract: A composition formed from (a.) aluminum oxide and/or a solid solution and/or a multiphase composition of aluminum oxide with one or more other metal oxide(s) and (b.) a metallic alloy and having a microstructure comprising a metallic phase, ceramic phase(s) comprising a reactive metal oxide phase and/or solid solutions containing said oxide, an aluminum oxide phase and/or solid solutions of aluminum oxide with one or more other metal oxides. The metallic alloy contains at least one metal characterized by a .DELTA.G of formation (Gibbs free energy) per mole of oxygen of its oxide that is comparable to or greater than the .DELTA.G of formation (Gibbs free energy) per mole of oxygen of aluminum oxide (133 Kcal/mole oxygen). The grain size of the ceramic phase(s) is less than about 10 microns. Cutting tools formed from these compositions have better operating lives than cutting tools containing tungsten carbide or titanium carbide.