Patent ID: 8715807

Claim:
A fused grain comprising an oxide phase of pseudo-brookite type, titanium, aluminum and magnesium, said fused grain having the following chemical composition, in weight percentages on the basis of the oxides: less than 52% of Al 2 O 3 ; more than 30% and less than 70% of TiO 2 ; more than 1% and less than 15% of MgO, said fused grain also corresponding to the following composition, in molar percentages and on the basis of the single oxides Al 2 O 3 , TiO 2 , MgO: 180≦3t+a≦220, a≦50, m=100−a−t in which: a is the molar percentage of Al 2 O 3 ; t is the molar percentage of TiO 2 ; m is the molar percentage of MgO.