1.The dredger could be divided into bucket type and pump suction type. Bucket type dredger is applied for waterways with high percentage of clay and gravels, while pump suction type can only be used for terrains with low percentage of clay and gravel. 2.Iron ore need to be retrieved firstly by magnetic separator if the percentage is high in the raw ore, then gold, diamond,zirconium will be concentrated. 3.The key part for the diamond dredger is pulsating jigger. The deal capacity decide the quantity of jigger. We learn the jigger’s technology from one engineer of South Africa. Now the diamond dredger is widely used in Africa.

The Gold and Diamond Washing Plants could be used to mine gold mixed with sand in palaeouchannel, palaeo-riverbed, alluvial placer, tailing after ball milling, and diamond and zirconium in raw ore. Iron ore need to be retrieved firstly by magnetic separator if the percentage is high in the raw ore, then gold ,diamond, zirconium will be concentrated, or the effectiveness will be affected. This set of mining equipment are composed of several gravity concentrators. The concentration ratio could reach as high as 1:1000, and the recovery efficiency about 90% after series of separation.