The Principal Methods of alluvial gold (placer gold) are gravity dressing. Now the most popular gold mining gravity equipment are: Sluice, Jigs, Shaking Table. In recent years, concentrator (centrifugal machine) is widespread used, and the effect is good. For improving gold mining condition, some institution, colloge and manufacuturer researched some high efficiency gold mining equipment. For instance, cross flow belt chute, short conical hydrocyclone, vibration chute, fluctuate sluice and etc.
Flotation mining, magnetic separation mining, electrostatic separation mining, amalgamation and chemical method are mainly used for separating ore concentrate.
For now, most alluvial gold mine are using Big Fixed Sluice/chute for roughing. Fixed sluice are simple design, no need for power, big capacity, for coarse granule, big concentration ratio, easy maintain and easy use. But high strength work are for sluice cleaning. Fixed Sluice can do nothing for fine gold. Generally, fixed sluice gold recover rate is lower than 50%.
Today fluctuate sluice almost replace fixed chute. Because fluctuate chute gold recover rate is more than 70%. And it is very easy for cleaning.
For concentrating, Concentrator, Jig and Shaking table are widely used.
Concentrator is for fine gold concentrating. It only handle material smaller than 5mm. It’s HIGHEST recover rate gold mining equipment. The recover rate is up to 98%. But the disadvantage is low capacity and expensive.
Compare to Shaking table, jigs become disuse. The advantage is big capacity and good gold recover rate(85-90%). Disadvantage is hard to use and maintain. For gold roughing, people use fluctuate sluice. For gold concentrating, shaking table is better.
The concentration ratio of shaking table is high, but capacity is low. So it can use for roughing. It’s mainly using for ore concentrating. Easy use, Easy maintain, low price, and gold recover rate is also upto 90%. Disadvantage, too low capacity.