The coinage metals comprise, at a minimum, those metallic

chemical element A chemical element is a species of atoms that have a given number of protons in their nuclei, including the pure substance consisting only of that species. Unlike chemical compounds, chemical elements cannot be broken down into simpler sub ...

s which have historically been used as components in

alloy An alloy is a mixture of chemical elements of which at least one is a metal. Unlike chemical compounds with metallic bases, an alloy will retain all the properties of a metal in the resulting material, such as electrical conductivity, ductilit ...

s used to mint coins. The term is not perfectly defined, however, since a number of metals have been used to make "demonstration coins" which have never been used to make monetized coins for any nation-state, but could be. Some of these elements would make excellent coins in theory (for example, zirconium), but their status as coin metals is not clear. In general, because of problems caused when coin metals are intrinsically valuable as commodities, there has been a trend in the 21st century toward use of coinage metals of only the least exotic and expensive types.

History

Historically, most coinage metals (or alloys) are from the three nonradioactive members of

group 11 Group 11, by modern IUPAC numbering, is a group of chemical elements in the periodic table, consisting of copper (Cu), silver (Ag), and gold (Au), and roentgenium (Rg), although no chemical experiments have yet been carried out to confirm that ...

of the

periodic table The periodic table, also known as the periodic table of the (chemical) elements, is a rows and columns arrangement of the chemical elements. It is widely used in chemistry, physics, and other sciences, and is generally seen as an icon of ...

: copper, silver and gold, the copper usually being augmented with tin and often other metals to form bronze. Gold, silver and bronze or copper were the coinage metals of the ancient world, and most medieval coins. All western histories of coins begin invention at some time slightly before or after 700 BC, in

Aegina Aegina (; el, Αίγινα, ''Aígina'' ; grc, Αἴγῑνα) is one of the Saronic Islands of Greece in the Saronic Gulf, from Athens. Tradition derives the name from Aegina, the mother of the hero Aeacus, who was born on the island a ...

Island, or, according to others, in

Ephesus Ephesus (; grc-gre, Ἔφεσος, Éphesos; tr, Efes; may ultimately derive from hit, 𒀀𒉺𒊭, Apaša) was a city in ancient Greece on the coast of Ionia, southwest of present-day Selçuk in İzmir Province, Turkey. It was built i ...

Lydia Lydia ( Lydian: ‎𐤮𐤱𐤠𐤭𐤣𐤠, ''Śfarda''; Aramaic: ''Lydia''; el, Λυδία, ''Lȳdíā''; tr, Lidya) was an Iron Age kingdom of western Asia Minor located generally east of ancient Ionia in the modern western Turkish provin ...

, 650 BC.

Ancient India According to consensus in modern genetics, anatomically modern humans first arrived on the Indian subcontinent from Africa between 73,000 and 55,000 years ago. Quote: "Y-Chromosome and Mt-DNA data support the colonization of South Asia by ...

in circa 6th century BC, was one of the earliest issuers of coins in the world. Since that time, coins have been the most universal embodiment of

money Money is any item or verifiable record that is generally accepted as payment for goods and services and repayment of debts, such as taxes, in a particular country or socio-economic context. The primary functions which distinguish money ar ...

. These first coins were made of

electrum Electrum is a naturally occurring alloy of gold and silver, with trace amounts of copper and other metals. Its color ranges from pale to bright yellow, depending on the proportions of gold and silver. It has been produced artificially, ...

, a naturally occurring pale yellow mixture of gold and silver that was further alloyed with silver and copper. However, the Persian daric was the first gold coin which, along with a similar silver coin, the

siglos The Achaemenid Empire issued coins from 520 BCE–450 BCE to 330 BCE. The Persian daric was the first gold coin which, along with a similar silver coin, the siglos (from grc, σίγλος, he, שֶׁקֶל, '' shékel'') represented the first ...

, (From

Ancient Greek Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic p ...

σίγλος,

Hebrew Hebrew (; ; ) is a Northwest Semitic language of the Afroasiatic language family. Historically, it is one of the spoken languages of the Israelites and their longest-surviving descendants, the Jews and Samaritans. It was largely preserved ...

שֶׁקֶל ( shékel)) represented the bimetallic monetary standard of the Achaemenid Persian Empire which has continued till today.Michael Alram
"DARIC"
'' Encyclopaedia Iranica'', December 15, 1994, last updated November 17, 2011 The

Persia Iran, officially the Islamic Republic of Iran, and also called Persia, is a country located in Western Asia. It is bordered by Iraq and Turkey to the west, by Azerbaijan and Armenia to the northwest, by the Caspian Sea and Turkme ...

n coins were also very well known in the Persian and

Sassanids The Sasanian () or Sassanid Empire, officially known as the Empire of Iranians (, ) and also referred to by historians as the Neo-Persian Empire, was the History of Iran, last Iranian empire before the early Muslim conquests of the 7th-8th cen ...

era. Most notably, in

Susa Susa ( ; Middle elx, 𒀸𒋗𒊺𒂗, translit=Šušen; Middle and Neo- elx, 𒋢𒋢𒌦, translit=Šušun; Neo-Elamite and Achaemenid elx, 𒀸𒋗𒐼𒀭, translit=Šušán; Achaemenid elx, 𒀸𒋗𒐼, translit=Šušá; fa, شوش ...

and in Ctesiphon. However, there are many more, even for coins made from intrinsically precious metals.

Precious metal Precious metals are rare, naturally occurring metallic chemical elements of high economic value. Chemically, the precious metals tend to be less reactive than most elements (see noble metal). They are usually ductile and have a high lu ...

s are always used in bullion coins and some collectable coins. Coins not intended for circulation or for intrinsic value have also been made experimentally using an even larger variety of metals, since they function as fiat money. In general coins intended for circulation must have metal values considerably less than their face values, for reasons discussed below.

Requirements for a coinage metal

Coins that are intended for circulation have some special requirements based on the conditions they will encounter. For example, a coin may be in circulation for up to 30 years, and so must have excellent wear resistance and anti-

corrosion Corrosion is a natural process that converts a refined metal into a more chemically stable oxide. It is the gradual deterioration of materials (usually a metal) by chemical or electrochemical reaction with their environment. Corrosion engi ...

properties. Achieving this goal necessitates the use of base metal

s. Some metals like manganese have occasionally been used in coins, but suffer from making the coins too hard to take an impression well (or metals apt to wear out stamping machines at the mint). When minting coins, especially low denomination coins, there is a risk that the value of metal within a coin is greater than the face value. This leads to the possibility of smelters taking coins and melting them down for the scrap value of the metal. Pre-1992 British pennies were made of 97% copper; but as of 2008, based on the price of copper, the value of a

penny A penny is a coin ( pennies) or a unit of currency (pl. pence) in various countries. Borrowed from the Carolingian denarius (hence its former abbreviation d.), it is usually the smallest denomination within a currency system. Presently, it is t ...

from this period is 1.5 new-pence. Modern British pennies are now made of copper-plated steel. For similar reasons, American pennies (cents) were once made of copper alloys, but since 1982 have been made of copper-plated zinc. This problem has led to nearly the end of use for a common base metal alloy for everyday coinage in the 20th century, called cupronickel, with varying proportions of

copper Copper is a chemical element with the symbol Cu (from la, cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish ...

and

nickel Nickel is a chemical element with symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel is a hard and ductile transition metal. Pure nickel is chemically reactive but large pieces are slow ...

, most commonly 75% Cu 25% Ni. Cupronickel has a silver color, is hard wearing and has excellent striking properties, essential for the

design A design is a plan or specification for the construction of an object or system or for the implementation of an activity or process or the result of that plan or specification in the form of a prototype, product, or process. The verb ''to design'' ...

of the coin to be pressed accurately and quickly during manufacture. In the 21st century with the prices of both copper and nickel rising, it has become more common to experiment with various alloys of steel, often stainless steel. For example, in India some coins have been made from a stainless steel that contains 82% iron, 18% chromium, and many other countries that have minted coins that contain metals now worth nearly the coin face-value, are experimenting with various steel alloys.

Chemical elements used in circulating coins

File:Obverse Of Token From 1887 American Exhibition In London England.jpg, An aluminium token coin from the 1887 American Exhibition in London. At the time, aluminium was complex to produce and more valuable than silver File:Se 5 öre 1950a.jpg, A 1950 iron

Swedish krona The krona (; plural: ''kronor''; sign: kr; code: SEK) is the official currency of the Kingdom of Sweden. Both the ISO code "SEK" and currency sign "kr" are in common use; the former precedes or follows the value, the latter usually follows it ...

coin, with face value of 5 öre File:Rio de Janeiro 4000 reis 1812 av.jpg, An 1812 gold 4000 réis coin from colonial Brazil File:BMC 193.jpg, Silver drachma from the island of

, after 404 BC File:Louis XIII Double Tournois, 1614 (35364492192) - 2.jpg, A 1614 copper double tournois from France

Non-circulating

Chemical elements used in non-circulating (commemorative, demo, bullion or novelty) coins, medals, patterns, and trial strikes: *

Cadmium Cadmium is a chemical element with the symbol Cd and atomic number 48. This soft, silvery-white metal is chemically similar to the two other stable metals in group 12, zinc and mercury. Like zinc, it demonstrates oxidation state +2 in most of ...

(1828 medal made by G. Loos for the marriage of Heinrich von Dechen, "of Silesian cadmium") *

Cobalt Cobalt is a chemical element with the symbol Co and atomic number 27. As with nickel, cobalt is found in the Earth's crust only in a chemically combined form, save for small deposits found in alloys of natural meteoric iron. The free element, ...

(2005 Cameroon 750 CFA francs struck in cobalt-plated iron.) *

Hafnium Hafnium is a chemical element with the symbol Hf and atomic number 72. A lustrous, silvery gray, tetravalent transition metal, hafnium chemically resembles zirconium and is found in many zirconium minerals. Its existence was predicted by D ...

(

Fred Zinkann Fred may refer to: People * Fred (name), including a list of people and characters with the name Mononym * Fred (cartoonist) (1931–2013), pen name of Fred Othon Aristidès, French * Fred (footballer, born 1949) (1949–2022), Frederico Rodr ...

demo coin.) * Iridium (2013 '' oz'' 10 franc bullion coin issued by Rwanda as part of "Noble Five" precious metals set.) *

Molybdenum Molybdenum is a chemical element with the symbol Mo and atomic number 42 which is located in period 5 and group 6. The name is from Neo-Latin ''molybdaenum'', which is based on Ancient Greek ', meaning lead, since its ores were confused with le ...

(Demo coin

) (Mintage 250-1 tr oz coins 2008 by Coins By DesignMurray Buckner.) * Niobium (Austria has issued a number of bimetallic 25 euro coins with a niobium center.) * Palladium (First issued 1966 by Sierra Leone. Also presentation sets from Tonga, bullion coins of various countries.) * Rhenium (

fantasy piecesPope Matthew Triple Ducat and Malvinas 5 Australes) * Rhodium (2014 '' oz'' 10 franc bullion coin issued by Rwanda as part of "Noble Six" precious metals set. Also Cohen Mint bullion round.) *

Ruthenium Ruthenium is a chemical element with the symbol Ru and atomic number 44. It is a rare transition metal belonging to the platinum group of the periodic table. Like the other metals of the platinum group, ruthenium is inert to most other chemic ...

(1967 '' Hau'' from Tonga was 98% palladium and 2% ruthenium) *

Selenium Selenium is a chemical element with the symbol Se and atomic number 34. It is a nonmetal (more rarely considered a metalloid) with properties that are intermediate between the elements above and below in the periodic table, sulfur and telluriu ...

(1862 medal in UK Science Museum, commemorating Berzelius, discoverer of the element.) *

Silicon Silicon is a chemical element with the symbol Si and atomic number 14. It is a hard, brittle crystalline solid with a blue-grey metallic luster, and is a tetravalent metalloid and semiconductor. It is a member of group 14 in the periodic ...

(Privately struck US quarter patterns dated 1964 (Pollock-5380) in nickel-silicon alloy.) * Tantalum (Used in a bimetallic silver-tantalum coin from Kazakhstan.) * Tellurium (1896 Hungarian mining medal. Reproductions exist from 1975.) *

Titanium Titanium is a chemical element with the Symbol (chemistry), symbol Ti and atomic number 22. Found in nature only as an oxide, it can be reduced to produce a lustrous transition metal with a silver color, low density, and high strength, resista ...

(First issued 1999 by Gibraltar. Austria has made bimetallic silver/titanium commemoratives.) *

Tungsten Tungsten, or wolfram, is a chemical element with the symbol W and atomic number 74. Tungsten is a rare metal found naturally on Earth almost exclusively as compounds with other elements. It was identified as a new element in 1781 and first isol ...

(Alloys are too hard. A few private demos struck only for experimentation.

US half eagle patterns.) *

Uranium Uranium is a chemical element with the symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Uranium is weakly ...

(Two types of a German medal of native uranium.) * Vanadium (Mintage 20-1 Troy ounce coins 2011 by Coins By DesignMurray Buckner.) * Zirconium (Mintage 500-1 Troy ounce coins 2012 including 50 black & 50 Rainbow by Coins By DesignMurray Buckner.)

Element Series

Beginning in 2006, Dave Hamric (Metallium) has been attempting to strike "coins" (technically tokens or medals, about the size of a US cent) of every stable chemical element. To date he has struck tokens of the following elements, apparently not only metals: *

Aluminium Aluminium (aluminum in AmE, American and CanE, Canadian English) is a chemical element with the Symbol (chemistry), symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately o ...

* Antimony * Barium (reactive, sealed in glass capsule) * Beryllium *

Bismuth Bismuth is a chemical element with the symbol Bi and atomic number 83. It is a post-transition metal and one of the pnictogens, with chemical properties resembling its lighter group 15 siblings arsenic and antimony. Elemental bismuth occurs ...

* Boron (mixed with binder, sealed in resin cast) *

Calcium Calcium is a chemical element with the symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar t ...

(reactive, sealed in glass capsule) *

Carbon Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent—its atom making four electrons available to form covalent chemical bonds. It belongs to group 14 of the periodic table. Carbon makes ...

(mixed with binder, sealed in resin cast) * Cerium (reactive, sealed in glass capsule) *

Chromium Chromium is a chemical element with the symbol Cr and atomic number 24. It is the first element in group 6. It is a steely-grey, lustrous, hard, and brittle transition metal. Chromium metal is valued for its high corrosion resistance and h ...

Copper Copper is a chemical element with the symbol Cu (from la, cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish ...

* Dysprosium * Erbium * Europium (reactive, sealed in glass capsule) * Gadolinium *

Gallium Gallium is a chemical element with the symbol Ga and atomic number 31. Discovered by French chemist Paul-Émile Lecoq de Boisbaudran in 1875, Gallium is in group 13 of the periodic table and is similar to the other metals of the group ( alum ...

Gold Gold is a chemical element with the symbol Au (from la, aurum) and atomic number 79. This makes it one of the higher atomic number elements that occur naturally. It is a bright, slightly orange-yellow, dense, soft, malleable, and ductile ...

* Holmium *

Indium Indium is a chemical element with the symbol In and atomic number 49. Indium is the softest metal that is not an alkali metal. It is a silvery-white metal that resembles tin in appearance. It is a post-transition metal that makes up 0.21 par ...

* Iridium *

Iron Iron () is a chemical element with symbol Fe (from la, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in ...

* Lanthanum (reactive, sealed in glass capsule) *

Lead Lead is a chemical element with the Symbol (chemistry), symbol Pb (from the Latin ) and atomic number 82. It is a heavy metals, heavy metal that is density, denser than most common materials. Lead is Mohs scale of mineral hardness#Intermediate ...

* Lutetium *

Magnesium Magnesium is a chemical element with the symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 of the periodic ...

* Mercury (sealed in resin cast) *

* Neodymium (reactive, sealed in glass capsule) *

Nickel Nickel is a chemical element with symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel is a hard and ductile transition metal. Pure nickel is chemically reactive but large pieces are slow ...

* Niobium * Palladium *

Phosphorus Phosphorus is a chemical element with the symbol P and atomic number 15. Elemental phosphorus exists in two major forms, white phosphorus and red phosphorus, but because it is highly reactive, phosphorus is never found as a free element on Ea ...

(mixed with binder, sealed in resin cast) *

Platinum Platinum is a chemical element with the symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal. Its name originates from Spanish , a diminutive of "silver". Pla ...

* Praseodymium (reactive, sealed in glass capsule) * Rhenium * Rhodium *

* Samarium (reactive, sealed in glass capsule) *

Scandium Scandium is a chemical element with the symbol Sc and atomic number 21. It is a silvery-white metallic d-block element. Historically, it has been classified as a rare-earth element, together with yttrium and the Lanthanides. It was discovere ...

Silver Silver is a chemical element with the Symbol (chemistry), symbol Ag (from the Latin ', derived from the Proto-Indo-European wikt:Reconstruction:Proto-Indo-European/h₂erǵ-, ''h₂erǵ'': "shiny" or "white") and atomic number 47. A soft, whi ...

Strontium Strontium is the chemical element with the symbol Sr and atomic number 38. An alkaline earth metal, strontium is a soft silver-white yellowish metallic element that is highly chemically reactive. The metal forms a dark oxide layer when it is ...

(reactive, sealed in glass capsule) *

Sulfur Sulfur (or sulphur in British English) is a chemical element with the symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms form cyclic octatomic molecules with a chemical formul ...

* Tantalum * Tellurium * Terbium *

Thallium Thallium is a chemical element with the symbol Tl and atomic number 81. It is a gray post-transition metal that is not found free in nature. When isolated, thallium resembles tin, but discolors when exposed to air. Chemists William Crookes a ...

(extremely poisonous. Lead token clad on one side with thallium foil and sealed in resin.) * Thulium * Tin *

(not offered for sale) * Vanadium * Ytterbium * Yttrium *

Zinc Zinc is a chemical element with the symbol Zn and atomic number 30. Zinc is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodic t ...

* Zirconium

Article "World's Coinage Uses 24 Chemical Elements"

World Coin News magazine published an article titled "World's Coinage Uses 24 Chemical Elements" by Jay and Marieli Roe, which appeared in two consecutive issues: Feb. 17, 1992, pages 24–25; and Mar. 2, 1992, pages 18–19. The article was based on an award-winning exhibit that was assembled by Jay and Marieli Roe (a.k.a. Dr. John Westel Rowe, an organic chemist in Wisconsin, and his wife Marieli Rowe), and shown during the 1987–1990 period. The 24 elements named are: Al, Sb, C, Co, Cu, Au, Hf, Fe, Pb, Mg, Mo, Ni, Nb, Pd, Pt, Re, Ag, Ta, Sn, Ti, W, V, Zn and Zr. The ANA did not award Best-of-Show "because the exhibit was downgraded for incompleteness" due to two missing pieces. However, the author defended his choices: The British Royal Mint's rhodium token "is only rhodium-plated", and the Pobjoy Mint's iridium coin "does not exist (possible confusion with palladium?)." Curiously, chromium and manganese were not mentioned, even though both elements had been used in common circulation coins (Canada wartime V nickels and US wartime Jefferson nickels, respectively) long before the time of the article's publication.

Non-metallic materials used for circulating coins

References

External links

Comprehensive list of metals and their alloys which have been used at various times, in coins for all types of purposes.
* {{in lang, fr}
Site of coinage metals and alloys