Abase metal is a common and inexpensivemetal, as opposed to aprecious metal such asgold orsilver.[1] Innumismatics, coins often derived their value from the precious metal content; however, base metals have also been used in coins in the past and today.[2]
In contrast tonoble metals, base metals may be distinguished byoxidizing orcorroding relatively easily and reacting variably with dilutedhydrochloric acid (HCl) to formhydrogen. Examples includeiron,nickel,lead andzinc.Copper is also considered a base metal because it oxidizes relatively easily, although it does not react with HCl.
Inmining andeconomics, the term base metals refers to industrialnon-ferrous metals excludingprecious metals. These include copper, lead, nickel and zinc.[3]
TheU.S. Customs and Border Protection agency is more inclusive in its definition of commercial base metals. Its list includes—in addition to copper, lead, nickel, and zinc—the following metals:iron andsteel (an alloy),aluminium,tin,tungsten,molybdenum,tantalum,cobalt,bismuth,cadmium,titanium,zirconium,antimony,manganese,beryllium,chromium,germanium,vanadium,gallium,hafnium,indium,niobium,rhenium, andthallium, and their alloys.[4]
In the context ofplated metal products, the base metal underlies the plating metal, as copper underlies silver inSheffield plate.