, the term base metal
is used informally to refer to a metal
relatively easily, and reacts variably with diluted hydrochloric acid
(HCl) to form hydrogen
. Examples include iron
is considered a base metal as it oxidizes relatively easily, although it does not react with HCl. It is commonly used in opposition to noble metal
In alchemy, a base metal was a common and inexpensive metal, as opposed to precious metals, mainly gold and silver. A longtime goal of the alchemists was the transmutation of base metals into precious metals.
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.
In mining and economics, base metals refers to industrial non-ferrous metals excluding precious metals. These include copper, aluminium, lead, nickel, tin and zinc.