Cupronickel (also known as copper-nickel) is an alloy of copper that contains nickel and strengthening elements, such as iron and manganese. Despite its high copper content, cupronickel is silver in colour.
Due to the specific properties of nickel and copper alloys, they are applied in various domains of industry e.g. coin and medal minting, armaments manufacture, desalination materials, marine engineering, and extensively used in the chemical, petrochemical and electrical industries.
Another common use of cupronickel is in silver-coloured modern-circulated coins. A typical mix is 75% copper, 25% nickel (a proportion of 3:1), and a trace amount of manganese. In the past, true silver coins were debased with cupronickel.
Aside from the terms cupronickel and copper-nickel, several other terms have been used to describe the material: the tradenames Alpaka or Alpacca, Argentan Minargent, and the French term cuivre blanc ("white copper") are still registered; cupronickel is also occasionally referred to as hotel silver, plata alemana (Spanish for "German silver"), German silver, and Chinese silver.