The invention relates to a mixture of fused grains mainly comprising or composed of an oxide phase of pseudo-brookite type and comprising titanium, aluminium and magnesium, said 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, said 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. The invention also relates to a ceramic product obtained from such fused grains.