Base metal

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A base metal is a common and inexpensive metal, as opposed to a precious metal such as gold or silver. [1] 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. [2]


Specific definitions

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.

In mining and economics, the term base metals refers to industrial non-ferrous metals excluding precious metals. These include copper, lead, nickel and zinc. [3]

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 (an alloy), 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. [4]

Other uses

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

See also

Related Research Articles

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Brass is an alloy of copper (Cu) and zinc (Zn), in proportions which can be varied to achieve different colours and mechanical, electrical, acoustic, and chemical properties, but copper typically has the larger proportion. In use since prehistoric times, it is a substitutional alloy: atoms of the two constituents may replace each other within the same crystal structure.

<span class="mw-page-title-main">Metal</span> Type of material

A metal is a material that, when freshly prepared, polished, or fractured, shows a lustrous appearance, and conducts electricity and heat relatively well. Metals are typically ductile and malleable. These properties are the result of the metallic bond between the atoms or molecules of the metal.

<span class="mw-page-title-main">Metallurgy</span> Field of science that studies the physical and chemical behavior of metals

Metallurgy is a domain of materials science and engineering that studies the physical and chemical behavior of metallic elements, their inter-metallic compounds, and their mixtures, which are known as alloys. Metallurgy encompasses both the science and the technology of metals; that is, the way in which science is applied to the production of metals, and the engineering of metal components used in products for both consumers and manufacturers. Metallurgy is distinct from the craft of metalworking. Metalworking relies on metallurgy in a similar manner to how medicine relies on medical science for technical advancement. A specialist practitioner of metallurgy is known as a metallurgist.

<span class="mw-page-title-main">Silver</span> Chemical element, symbol Ag and atomic number 47

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<span class="mw-page-title-main">Solder</span> Alloy used to join metal pieces

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Cupronickel or copper-nickel (CuNi) is an alloy of copper with nickel, usually along with small quantities of other elements added for strength, such as iron and manganese. The copper content typically varies from 60 to 90 percent.

<span class="mw-page-title-main">Nickel silver</span> Shiny alloy of copper, nickel, and zinc

Nickel silver, maillechort, German silver, argentan, new silver, nickel brass, albata, or alpacca is a copper alloy with nickel and often zinc. The usual formulation is 60% copper, 20% nickel and 20% zinc. Nickel silver does not contain the element silver. It is named for its silvery appearance, which can make it attractive as a cheaper and more durable substitute. It is also well suited for being plated with silver.

<span class="mw-page-title-main">Brazing</span> Metal-joining technique

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<span class="mw-page-title-main">Tombac</span> Copper-zinc alloy

Tombac, or tombak, is a brass alloy with high copper content and 5–20% zinc content. Tin, lead or arsenic may be added for colouration. It is a cheap malleable alloy mainly used for medals, ornament, decoration and some munitions. In older use, the term may apply to brass alloy with a zinc content as high as 28–35%.

<span class="mw-page-title-main">Scrap</span> Recyclable materials left over from manufactured products after their use

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This glossary of numismatics is a list of definitions of terms and concepts relevant to numismatics and coin collecting, as well as sub-fields and related disciplines, with concise explanations for the beginner or professional.

In metallurgy, non-ferrous metals are metals or alloys that do not contain iron in appreciable amounts.

<span class="mw-page-title-main">Glass-to-metal seal</span> Airtight seal which joins glass and metal surfaces

Glass-to-metal seals are a type of mechanical seal which joins glass and metal surfaces. They are very important elements in the construction of vacuum tubes, electric discharge tubes, incandescent light bulbs, glass-encapsulated semiconductor diodes, reed switches, glass windows in metal cases, and metal or ceramic packages of electronic components.

<span class="mw-page-title-main">Amalgam (chemistry)</span> Alloy of mercury with another metal

An amalgam is an alloy of mercury with another metal. It may be a liquid, a soft paste or a solid, depending upon the proportion of mercury. These alloys are formed through metallic bonding, with the electrostatic attractive force of the conduction electrons working to bind all the positively charged metal ions together into a crystal lattice structure. Almost all metals can form amalgams with mercury, the notable exceptions being iron, platinum, tungsten, and tantalum. Silver-mercury amalgams are important in dentistry, and gold-mercury amalgam is used in the extraction of gold from ore. Dentistry has used alloys of mercury with metals such as silver, copper, indium, tin and zinc.

Tibetan silver in modern usage refers to a variety of white non-precious metal alloys used primarily in jewelry components, with an appearance similar to aged silver.

<span class="mw-page-title-main">Group 11 element</span> Group of elements in the periodic table

Group 11, by modern IUPAC numbering, is a group of chemical elements in the periodic table, consisting of copper (Cu), silver (Ag), gold (Au), and roentgenium (Rg), although no chemical experiments have yet been carried out to confirm that roentgenium behaves like the heavier homologue to gold. Group 11 is also known as the coinage metals, due to their usage in minting coins—while the rise in metal prices mean that silver and gold are no longer used for circulating currency, remaining in use for bullion, copper remains a common metal in coins to date, either in the form of copper clad coinage or as part of the cupronickel alloy. They were most likely the first three elements discovered. Copper, silver, and gold all occur naturally in elemental form.

The coinage metals comprise those metallic chemical elements and alloys which have been used to mint coins. Historically, most coinage metals are from the three nonradioactive members of group 11 of the periodic table: copper, silver and gold. Copper is usually augmented with tin or other metals to form bronze. Gold, silver and bronze or copper were the principal coinage metals of the ancient world, the medieval period and into the late modern period when the diversity of coinage metals increased. While coins are primarily made from metal, some non-metallic materials have also been used.

<span class="mw-page-title-main">Lead smelting</span> Process of refining lead metal

Plants for the production of lead are generally referred to as lead smelters. Primary lead production begins with sintering. Concentrated lead ore is fed into a sintering machine with iron, silica, limestone fluxes, coke, soda ash, pyrite, zinc, caustics or pollution control particulates. Smelting uses suitable reducing substances that will combine with those oxidizing elements to free the metal. Reduction is the final, high-temperature step in smelting. It is here that the oxide becomes the elemental metal. A reducing environment pulls the final oxygen atoms from the raw metal.

<span class="mw-page-title-main">Non-ferrous extractive metallurgy</span> Metallurgy process

Non-ferrous extractive metallurgy is one of the two branches of extractive metallurgy which pertains to the processes of reducing valuable, non-iron metals from ores or raw material. Metals like zinc, copper, lead, aluminium as well as rare and noble metals are of particular interest in this field, while the more common metal, iron, is considered a major impurity. Like ferrous extraction, non-ferrous extraction primarily focuses on the economic optimization of extraction processes in separating qualitatively and quantitatively marketable metals from its impurities (gangue).


  1. Oxford dictionary definition of "base metal" [ dead link ]
  2. "Introduction to Numismatic Terms and Methods". Archived from the original on 20 October 2021. Retrieved 20 October 2021.
  3. "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.
  4. What Every Member of the Trade Community Should Know About: Household Articles of Base Metal, U.S. Customs and Border Protection. Jan. 2010