Raymond (Raymond) common sense: Hardness: Because it is destructive test, so the unground of the original stone or precious of minerals can be used. There are two types of hardness scales, one is the absolute hardness of stone mill, and the other is a Mohs hardness (a relatively hardness) Mohs hardness: Ten to common mineral used as a standard to distinguish scratch with each other what what hard soft vertical milling machine, it is customary on mineralogy or gemology is Mohs hardness. Mesh sieve pore is a general characterization of the size of its conversion formula is cm = 16 / mesh industrial milling machines, mesh has British and US mills, Imperial refers to the number of holes per square inch; Zhengzhou Lei machinery High Pressure Equipment Co., conventional micro-grinding abrasive material suitable for grinding, such as kaolin, limestone, calcite, marble, barite, gypsum, iron oxide, iron oxide green, aluminum hydroxide, pigment, clay, coal, activated carbon, etc. humidity is less than 8%, Mohs hardness of ultra-fine powder processing of non-inflammable in 6 below. Pressure micro-grinding type: YGM7826, YGM8327, YGM9531 like. Milling machine manufacturers | mill | Lei Lei machinery is provided by Zhengzhou Machinery Co., Ltd.. Zhengzhou Lei Machinery Co., Ltd. (www.hnzljx.net) (www.hnzljx.net) strong, credible, in Zhengzhou, Henan crushing grinding equipment industry has accumulated a large number of loyal customers. The company better work attitude and constantly improving innovative ideas will lead Lei machinery into the brilliant and you work for a better future!