Here is a review of various gold recovery machines/methods and the gold particle size they are best suited to recover.  Compare Jig, shaker tables, dry washer, sluice box, spirals, bowl concentrators, falcon, Knelson and leaching.

The size distribution of the raw material will also determine if classification of the ore is necessary for better recovery. The processing capacity of the equipment must conform to the mining plan. Cleaners usually have relatively low capacities and may limit the total amount of ore that can be processed. Finally, as important as the recovery efficiency of the equipment is, in some cases, most notably with high volume operations, optimum recovery is sometimes sacrificed for increased capacity. Also, efficiency can be affected by factors not controlled by the device, such as feed-flow rates.

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COMPARE GRAVITY GOLD CONCENTRATION METHODS