The beneficiation of ultrafine vertical mill ore is based on the difference in physical properties of minerals, such as the difference in particle size, shape and specific gravity, the gravity separation is the main method of placer alluvial gold beneficiation processing.Commonly used gravity separation equipment includes chute (sluice), various types of mineral jigs, gold shakers, centrifugal concentrators, etc. 

According to the working principles, the gravity separation process can be divided into ore washing, particle grading, gold sluice, gold jig, gold shaker and heavy medium separation. Among them, except for washing and grading, which are mainly separated by particle size, the other is the process of separating the minerals by specific gravity (density).