How are heavy minerals mined in Florida?
Prior to mining the trees are harvested by normal silvicultural practices. One foot of topsoil is removed and stockpiled along the edge of the mine for later use in reclamation. The topsoil storage piles are also used to contain sediment and stormwater within the project limits. The heavy minerals occur as sand grains mixed in with lighter clays and quartz sand grains. Within the ore body, less than 5 percent of the grains may be heavy minerals. Above the ore body is the overburden of clays and quartz sand without marketable product. Two mining methods are used: suction dredging and auxiliary mining. • In the suction dredging method, an electrically powered suction dredge floats within a 15- to 20-acre man-made pond. At one end of the pond, the dredge draws in overburden, ore and water and transfers the mixture to a floating wet mill. Vibrating screens block out roots and other large objects. Spiral centrifuges are then used to concentrate and separate the heavy mineral sands from the
