Cupronickel

Copper nickel or technical terminology correctly copper-nickel- iron alloys are standardized with nickel contents of 10, 20 and 30 %. A low silicon content is permitted. The alloys are characterized by high corrosion resistance against seawater.

Because of their decorative appearance and utility and decorative items are often made ​​from such alloys.

They have meaning in coinage, as modern coins are made ​​of a wrought alloy CuNi25, ie an alloy of the metals copper (Cu ) and nickel ( Ni).

Copper has been used since ancient times as a material for coins, pure nickel there was because of its high melting point as an alloying element, however, not yet, although the copper nickel matte was already known. For valuable coins were silver and gold using copper increases even at a nickel content of <15% a silvery color. Coins from a copper -nickel alloy have largely replaced the hitherto customary for higher denominations of silver coins in the last century.

In euro coins CuNi25 the alloy is used for both the ring of 2- euro coin as well as the core of the 1- euro coin. The Swiss circulation coins of ten cents piece to the five-franc piece also made of this alloy.