Patent ID: 7402543

Claim:
A refractory tile made from at least a three (3) hour long, high temperature firing of a clay body having the following dry clay base composition: 0.76 to 0.84% by weight Sodium Oxide (Na 2 O); 1.06-1.18% by weight Potassium Oxide (K 2 O); 0.14-0.16% by weight Magnesium Oxide (MgO); 0.15-0.19% by weight Calcium Oxide (CaO); 27.09-29.95% by weight Aluminum Oxide (Al 2 O 3 ); 1.05-1.17% by weight Ferric Oxide (Fe 2 O 3 ); 63.46-70.14% by weight Silicon Dioxide (SiO 2 ); 0.75-0.83% by weight Titanium Dioxide (TiO 2 ); 0.019-0.021% by weight Phosphorus Pentoxide (P 2 O 5 ); and 0.50-0.56% by weight Organic material.