Patent ID: 8258068

Claim:
A sintered product elaborated from a starting charge containing 75-99% of zircon, in mass percentage based on the oxides and in which raw materials are powders having a median size of less than 5 μm, said sintered product having the following average weight chemical composition in mass percentages based on the oxides: 60%≦ZrO 2 ≦72.8%, 27%≦SiO 2 ≦36%, 0.1%≦B 2 O 3 +GeO 2 +P 2 O 5 +Sb 2 O 3 +Nb 2 O 5 +Ta 2 O 5 +V 2 O 5 , 0.1%≦ZnO+PbO+CdO, B 2 O 3 +GeO 2 +P 2 O 5 +Sb 2 O 3 +Nb 2 O 5 +Ta 2 O 5 +V 2 O 5 +ZnO+PbO+CdO≦5% 0%≦Al 2 O 3 +TiO 2 +MgO+Fe 2 O 3 +NiO+MnO 2 +CoO+CuO≦5%, other oxides: ≦1.5%, for a total of 100%.