Patent ID: 8288300

Claim:
A fused cast refractory product with a high zirconia content comprising, as a percentage by weight based on the oxides and for a total of more than 98.5%: ZrO 2 + Hf 2 O: >85%; SiO 2 : >10% to 12%; Al 2 O 3 : 0.1% to 2.4%; B 2 O 3 : <1.5%; and a dopant selected from the group consisting of V 2 O 5 , CrO 3 , Nb 2 O 5 , MoO 3 , Ta 2 O 5 , WO 3 , and mixtures thereof, in a weighted quantity as expressed below: 2.43V 2 O 5 +4.42CrO 3 +1.66Nb 2 O 5 +3.07MoO 3 +Ta 2 O 5 +1.91WO 3 â‰§0.2%.