Base metal

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In chemistry, the term base metal is used informally to refer to a metal that oxidizes or corrodes relatively easily and reacts variably with diluted hydrochloric acid (HCl) to form hydrogen. Examples include iron, nickel, lead and zinc. Copper is also considered a base metal because it oxidizes relatively easily, although it does not react with HCl.

Other usages[edit]

Base is used in the sense of low-born, in opposition to noble or precious metal.[1] In alchemy, a base metal was a common and inexpensive metal, as opposed to precious metals, mainly gold and silver. A long-time goal of the alchemists was the transmutation of base metal into precious metal.

In numismatics, coins used to derive their value primarily from the precious metal content. Most modern currencies are fiat currency, allowing the coins to be made of base metal.[citation needed]

In mining and economics, the term base metals refers to industrial non-ferrous metals excluding precious metals. These include copper, lead, nickel and zinc.[2] The U.S. Customs and Border Protection is more inclusive in its definition. It includes, in addition to the four above, iron and steel, aluminium, tin, tungsten, molybdenum, tantalum, cobalt, bismuth, cadmium, titanium, zirconium, antimony, manganese, beryllium, chromium, germanium, vanadium, gallium, hafnium, indium, niobium, rhenium and thallium.[3]

In the context of plated metal products, the base metal underlies the plating metal, as copper underlies silver in Sheffield plate.

Zamak is an alloy used in casting (metalworking) which is sometimes called 'base metal' or deprecated as 'muckite'.[citation needed]

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