Cadmium is largely obtained from residues of the extraction of zinc, copper or lead, usually by distillation or electrolysis.
Cadmium resembles zinc in appearance but is softer. It is largely used to coat other metals (by spraying or electro-deposition), as a de-oxidant in the manufacture of copper, silver, nickel, etc. Because of its very high rate of absorption of slow neutrons, it is also used for the manufacture of mobile control and monitor rods for nuclear reactors. The principal cadmium alloys which may fall in the heading in accordance with Note 5 to Section XV are cadmium-zinc alloys used for hot-dip anti-corrosion coating, as solders and for brazing. Other alloys containing the same metals (e.g., certain bearing alloys) may, however, be excluded.
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