The process involved in concentration, recovery and separation stages is based on the concept of Gravity Separation (Gravity Concentration). Gravity separation has been tested and approved as one of the best techniques for the concentration of free flowing minerals. It is one of the oldest recovery methods in the mining and has been used as a primary form of mineral concentration for centuries, dating back to ancient Egypt.
This separation method consists in separating minerals or metals from one another based on their specific gravity and their relative response to other forces.
Concentration Criterion (CC) is commonly used to determine the suitability of gravity separation processes to a particular ore type.
Gold recovery on DOVE concentrating table.
Concentration Criterion for some minerals separated by gravity separation from a gangue of density 2,650 kg/ m3
| MINERAL | MEDIUM | CONCENTRATION CRITERION (CC) |
| Gold | Water | 10.3 |
| Gold | Air | 6.8 |
| Cassiterite | Water | 3.5 |
| Hematite | Water | 2.5 |
In a Gravity Separation process, the metals and minerals are subjected to forces in a medium, such as water, air, or other heavy medium. The response of the minerals and metals to these forces can be enhanced resistance or settling velocity, depending on their specific gravity, which will allow for the separation to occur. This way, valuable minerals and the gangue can be separated from one another due to their difference in specific gravity and response to the various forces in the medium. Due to its high efficiency and low cost, gravity separation has always been the first method of concentration that is considered when designing a mineral processing plant.
DOVE Processing plants (Wash Plants) utilize Gravity separation for the recovery of gold and other minerals from alluvial deposits, which requires less capital investment and provides better security for the high value production concentrates.
Another advantage is low environmental impact of gravity plant effluent, due to the absence of chemicals.