... .Great thermostability 3.High strength,hardness,density zirconia ceramic ball,white ceramic balls,Zirconium Oxide Ceramic BallCeramic balls are widely used as grinding mediums ... , HNCC Zirconia Ball, Best grinding Medium, HNCC Zirconia Ceramic Ball2.MaterialYttria stabilized Zirconium, yttria stabilized Dioxide3.CertificateISO9001,ISO140014.Density: ≥5.95 g ...