Oct 03, 2012 · T he DRC is Africa's largest copper producer and the world's largest cobalt producer. Its mining sector contributes 22% of .
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Ironsand also known as ironsand and iron sand is a type of sand with heavy concentrations of is typically dark grey or blackish in colour. It is composed mainly of magnetite, Fe 3 O 4, and also contains small amounts of titanium, silica, manganese, calcium and vanadium.. Ironsand has a tendency to heat up in direct sunlight, .
Placer deposit: Placer deposit, natural concentration of heavy minerals caused by the effect of gravity on moving particles. When heavy, stable minerals are freed from their matrix by weathering processes, they are slowly washed downslope into streams that quickly winnow the lighter matrix. Thus the heavy minerals
Magnetite is sometimes found in large quantities in beach sand. Such black sands (mineral sands or iron sands) are found in various places, such as Lung Kwu Tan of Hong Kong; California, United States; and the west coast of the North Island of New Zealand. The magnetite, eroded from rocks, is carried to the beach by rivers and concentrated .