A base metal is a common and inexpensive metal, as opposed to a precious metal such as gold or silver. In numismatics, coins often derived their value from the precious metal content; however, base metals have also been used in coins in the past and today.
In contrast to noble metals, base metals may be distinguished by oxidizing or corroding relatively easily and reacting 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.
The U.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 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, and their alloys.
- Oxford dictionary definition of "base metal" oxforddictionaries.com.
- "Introduction to Numismatic Terms and Methods". numismatics.org. Retrieved 20 October 2021.
- "Base Metal and Iron Ore Mining, Pollution Prevention and Abatement Handbook. WORLD BANK GROUP 1998" (PDF). Archived from the original (PDF) on 2016-09-09. Retrieved 2010-06-02.
- What Every Member of the Trade Community Should Know About: Household Articles of Base Metal, U.S. Customs and Border Protection. Jan. 2010