A mixture of fused grains mainly comprising or composed of an oxide phase of pseudo-brookite type and comprising titanium, aluminum and magnesium, the fused grains having the following chemical composition, in weight percentages on the basis of the oxides: less than 55% of Al2O3; more than 30% and less than 70% of TiO2; more than 1% and less than 15% of MgO, the fused grains also corresponding to the following composition, in molar percentages and on the basis of the single oxides Al2O3, TiO2, MgO: 180≦3t+a≦220, a≦50, m=100−a−t, in which: a is the molar percentage of Al2O3; t is the molar percentage of TiO2; m is the molar percentage of MgO. A ceramic product obtained from such fused grains.