Mining Free Gold
The following pages explain details about exploring free gold, as a byproduct, from sand and gravel mining operations. The following information is based on the actual revitalization of gold at sand and gravel plants placed on rivers. These rivers drain areas which actively sustained gold mining at one time. Related areas should present comparable results, but in that case a lot of drainage systems will not contain sufficient gold to make attempted recovery lucrative. Enough gold must be in the area to be commercially recovery. Extensive sampling of the sand and gravel site must be carried out to decide the financial possibility of keeping gold as byproduct.
The range of the gold elements recovered at this location varies from a very fine 400 mesh (a screen which has 400 openings to the inch) to 10 mesh. The gold transient through 400 meshes is very fine whereas the leafy flakes hardly able to pass through 10 meshes are pretty visible. Rarely bigger particles are recovered.
The gravel plants as a rule, turn out different sized products, these are 1 ¼ inch combined and the finer sand, which go by through a ¾ inch screen. Because the gold is fine, all the gold is in the sand product. The majority rule of milling and heavy metal separation embrace true: there can’t be no concentration without size classification. The rag plant utilize to grab gold is set up on this 3/8 inch screened product. A rag plant is a steel launder; it’s a large flat-bottomed trough which is set to adequate the angles so that the water can carry sand from the upper to the lower end. This launder is used to carry the sand, but it is also the place where any gold can be dividing from the sand. Rag plants sizes vary according to how much sand the sand is development per hour, and how much water is used to bring the sand. A big operation (200 tons per hour) may need a rag plant 8 feet wide, 50 feet long and 10 inches deep. Sand and gravel plants use smaller tonnage, and do not require a big rag plant. Still to guarantee maximum gold recovery, the rag plant must be at least 30 feet long. With shorter distances is very possible to lose amounts of gold.