1.1This classification covers fired refractory brick and shapes consisting predominantly of zircon (ZrO2·SiO 2) and containing, by chemical analysis, not less than 60 % zirconium oxide (ZrO2) and not less than 30 % silica (SiO 2).
1.2The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.
