Division standards of all kinds of mineral hardness in Mill machinery:
Because this test is destructive to materials, it can only be made on the original stones or not precious ores. Hardness can be divided in to two kinds, one is absolute hardness, and the other is Mohs scale of mineral hardness (a relative hardness).
Mohs scale of mineral hardness:
Distinguish the hardness among ten common minerals by scratching one to another. Mohs hardness is usually applied in mineralogy and gemology.
Mohs scale of mineral hardness has ten grades. They are talc, gypsum, calcite, fluorite, apatite,orthoclase feldspar, quartz, topaz, corundum and diamond.
Mohs hardness is often mentioned Mill Machinery. It is a kind of relative hardness, proposed by the German mineralogist Mohs (Frederich Mohs) in 1824. It characterizes the scratch resistance of various minerals through the ability of a harder material to scratch a softer material. Scratch method will be diamond needle score try mineral of surface scratches, with ten levels depth of the scratches representing the hardness. They are talc 1, gypsum 2, calcite 3, fluorite 4, apatite 5, orthoclase feldspar 6, quartz 7, topaz 8, corundum 9 and diamond 10.
According to different hardness, different minerals need specific crushers. Mill machines are to overcome specific force, and also have different fineness or production.