Gold prospecting in beach is an accumulation of valuable minerals formed by gravity separation during sedimentary processes and in geology called placer deposits . Beach placers form on seashores where wave action and shore currents shift materials, the lighter more rapidly than the heavier, thus concentrating gold .
Placer environments typically contain black sand, a conspicuous shiny black mixture of iron oxides, mostly magnetite with variable amounts of ilmenite and hematite. Valuable mineral components often occurring with black sands are monazite, rutile, zircon, chromite, wolframite, and cassiterite.
Among the examples of beach placers are the gold deposits of Nome, Alaska; the zircon sands of Brazil and Australia; the black sands (magnetite) of Oregon and California; and the diamond-bearing marine gravels of Namaqualand, South Africa.