Alluvial gold mining using modern methods utilized by big and small gold mining companies will be our focus in this article since we have covered the local methods of mining in Africa and other regions in the world.
The principles are the same the major difference is that all the equipment is replaced from local to modern for ease of mining operation and to increase gold production by reducing overhead cost of operation.
Instead of digging the gold mine with Shovel or Holes to reach the AU (Gold Bearing deposit) materials, this mining operation employs the use of an excavator to dig the mine to the depth where the AU material is deposited.
The excavator does double tasks, it replaces the bows, shovels, etc, used by local miners to convey the AU materials to the washing board, by digging down the depth where the Au materials are deposited in the mine and stockpiling the AU materials in a location where a backhoe can easily transfer these materials into a Wash Plant Machine, and in this case, the Wash Plant Machine replaces the washing board.
The Wash Plant Machine processed the gold from the AU materials ( (gold mixed with sand, gravel, and clay) faster than the local washboard. Some have the capacity to process 1000tph or more whereas the local mining methods would hardly exceed processing 50 tons of the AU materials for a whole day of mining operations.
Let me break it down, for example, if mining operation last for probably 8 hours a day, it means that local mining operation would have processed 50 tons of AU materials with a lot of workers pouring out the materials into the washboard, production of the gold process would amount to 50x8=400tons for a full day production, However with just a few staff, the backhoe operator and the operator of the washplant machine with the capacity of 1000tph.
which means, for a full day operation of 8hours the amount of gold processed: is 8x1000=8000tons of AU which is a huge difference relative to local mining that would hardly process 50tons of AU for a full-day operation.
Below are some images of mechanized Alluvial gold mining operation images ...
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Here you can see above the excavator stockpiling the AU materials.
As you can see above this small washing plant washes AU materials 100tph and all washing plant has a sluice section for trapping gold particles pouring out of the washing machine. You can see the gold mat and those metal locks on the top of the mat trap various sizes of gold, just like the local mining operation but this catches more gold faster and even finer gold particles.
As you can see above the backhoe here convey these stockpiles of AU materials into the wash plant to process it, in some cases, the excavator feeds the backhoe directly after stockpiling the AU materials to keep the operation simple and faster depending on what works best for the mining operation to increase production. Ensuring whenever purchasing excavator purchased the one that has a bigger bucket with longer hand, this will cover a longer distance and convey the larger quantity of the AU materials thereby increasing productivity.