1.1本分类涵盖主要由锆石（ZrO2[dot]SiO2）组成的烧结耐火砖和形状，通过化学分析，其含有不低于60%的氧化锆（ZrO2）和不低于30%的二氧化硅（SiO2）。

1.1 This classification covers fired refractory brick and shapes consisting predominantly of zircon (ZrO2[dot]SiO2) and containing, by chemical analysis, not less than 60% zirconium oxide (ZrO2) and not less than 30% silica (SiO2).