With an aluminium oxide content of less than 98,5 % by weight
Artificial corundum, whether or not chemically defined, with > 50 % of the total weight having a particle size > 10 mm (excl. with an aluminium oxide content > 98,5% by weight "high purity")
Artificial corundum, whether or not chemically defined, with < 50 % of the total weight having a particle size > 10 mm (excl. with an aluminium oxide content > 98,5% by weight "high purity")