The gravity separation sorts minerals based on differences in their relative densities (usually called specific gravity). Mineral particles with different densities are affected by fluid dynamics and various mechanical forces in the moving medium (water, air and heavy liquid), resulting in suitable loose stratification and separation conditions, so that mineral particles with different densities can be separated.
It is one of the oldest and most common methods of benificate gold. In placer gold ore, gold usually exists in the form of single nature of which density is generally more than 16t/m³, which is very different from the density of gangue. Therefore, the gravity separation is the most important, effective and economical method for sorting placer gold ores. However, in vein gold mines, gravity separation is rarely used alone. It is generally used as part of the joint gold extraction process.
Generally, in the grinding and grading circuit, jigger and spiral chute are used with a shaking table to recover the dissociated material in advance. Coarse-grained single gold to facilitate subsequent flotation and cyanidation operations and obtain qualified gold concentrate. This method is more commonly used in small-scale gold mines and local group mining, so it is relatively common in Africa.
