Zirconium oxide
Commonly called zirconia, it is a white crystalline solid with a hardness level of 6.5 on the Mohs scale. At an ambient temperature it has a monoclinic form, can be stabilised in a tetragonal or cubic form through addition of metallic oxides like calcium, magnesium or yttrium with increase in the hardness up to 8 on the Mohs scale.
Tags: ABRASIVES AND ABRASIVE GRINDERS, abrasives, FRICTION MATERIALS, ceramic materials