In the mining industry where large volumes of grinding media per mill are required, media wear versus cost is a key optimization consideration. Quantification of in-plant media wear is, however, often problematic. It can be done indirectly via small-scale laboratory mill tests or potentially via measurement of the physical and mechanical properties of the media: size, density, sphericity, hardness, toughness, etc. While some of these parameters are easily quantifiable, hardness and toughness as indicators of media wear are not as straightforward. The importance of hardness and toughness of grinding media in the stirred-mill environment are explained as well as the considerations that should be borne in mind when using these measurements as quality parameters. These considerations are given against the background of the various manufacturing methods of ceramic grinding media and the influence thereof on media quality.