Micro powder grinding mill, as we all know that it’s one of common use micro minerals powder grinding machines, can be used in more than 150 kinds of minerals powder grinding. However, not all kinds of minerals can be grind by our micro powder grinding mill, the HGM micro powder grinding mill can grind minerals into 300-2500 mesh micro powder, but if you want to process hardness more than Mohs’ 6, that will cause a much worn of micro powder grinding mill. Mohs’ hardness is used for measure the minerals’ hardness, it was divided into 10 grades, take talc as an example, it’s hardness is Mohs’ 1, and the hardest material on the world is diamond, it’s Mohs’ 10; and that interesting, our skin hardness is Mohs’ 2, it’s more harder than talc is. So our micro powder grinding mill can be used in Mohs’ hardness less than 6 minerals, there are about 150 kinds of minerals on the earth, such as: talc, dolomite, limestone, calcium carbonate, carbon black, graphite, calcite and so on. However, there are also some other minerals Mohs’ more than 6, but can be sued in our micro powder grinding mill to process powder, but it will cause much worn, so we don’t recommend you to process these materials by our HGM micro powder grinding mill.