A bright silver-white metallic element of atomic number 28. It is of the iron group, and is hard, malleable, and ductile. It occurs combined with sulphur in millerite, with arsenic in the mineral niccolite, and with arsenic and sulphur in nickel glance. Symbol Ni. Atomic weight 58.70.

This metal offers combination of corrosion resistance, formability and tough physical properties. For these reasons, nickel is used for alloying purposes and in nickel-clad copper wire.

An element, Ni, used in alloys and electroplating.

Widely used as an alloying element in steels. Up to 5.0% can be present in general engineering and in case-hardening steels. Improves strength and toughness and increases hardenability. Larger amounts are present in austenitic stainless and in heat resisting steels. Also used in Invar, a controlled thermal expansion alloy, and in permanent magnet alloys.

A small coin made of or containing nickel; esp., a five-cent piece.

Five dollars, in chip form usually red in color.

Dealer slang for $5 gaming cheques

Five dollars, usually represented by a red casino check.

Not found in water sources; traces in drinking water, which do not present a risk to health, are derived from protective coatings on taps and fittings. 50 µg/l

Nickel is a trace mineral.

annabergite, Ni3As2O2.8H2O, a green mineral ( nickel bloom)