Mineral processing, art of treating crude ores and mineral products in order to separate the valuable minerals from the waste rock, or gangue. It is the first process that most ores undergo after mining in order to provide a more concentrated material for the procedures of extractive metallurgy.
Size reduction in impact crushers occurs through particle concussion by rigid forces. The hammer crusher , also called the hammer mill, is an example of an impact crusher. In hammer crushers, hammers swing freely on a disc mounted on the main shaft within the device .