Posts Tagged ‘ancient coins’

This is the second of several reports on the basic information, the basic knowledge of minting coins and medals. These facts are so important they should be embedded in the repertoire of everyone associated with the medallic field and, certainly, everyone within the firms which make these.

COMPOSITION is the material of which coins and medals are made. Numismatists use that term where others might think of “metals” or “alloys.” The broader term is used because medals are infrequently made of nonmetal material, as will be mentioned. The other meaning of the term “composition” – the arrangement of elements in a design – should not be used in numismatics to lessen the confusion between the two meanings.

Note that the metals used for ancient coins, even hundreds of years before the birth of Christ are still those same metals used for coins and medals today:  gold, silver and bronze. The ancients did not have some great insight, but rather they had metalworking experience.

These metals had been worked by man for centuries before (as early as 4,000 BC for bronze. China’s choice for early coins was bronze, India was silver, western countries preferred precious metals silver and gold. These three metals, employed for the world’s earliest coins, possessed the most desirable characteristics required for coin making. They also possessed desirable wearing qualities for circulating, then as now.

Metals In A Coinage System.
As coins of different denominations were created to facilitate commerce, a  coinage system was established. Higher denominations required more costly metals. Thus two and three metals were employed. These could be coins of pure metals or several metals combined to form an alloy in which to strike the coins.

A coinage system that employs two metals, as gold and silver, is called a binary system. The Lydians, who first struck coins in 640 BC, developed such a two-metal binary system in 550 BC.  When a system has three metals, as gold, silver and bronze – or any three metals pure or alloyed – for its coins is said to be on a ternary system. If four metals are employed it is a quaternary system.

In 1920 Great Britain reduced the precious metal content of their coins by half, going off the sterling standard. They went from a ternary to a quaternary system. They continued striking .500 silver coins, with additional alloys, but eliminated silver entirely in 1946. Their crowns and shillings, formerly struck in silver were thereafter struck in copper-nickel. (Their coinage system was decimalized in 1968, but their coins still continue to be struck in copper-nickel.)

(Clad compositions, which became popular in the late 20th century, have obscured these “-nary” designations; future metallurgical grammarians will be required to redefine these terms.)

Coinage Metal Alloys.
The earliest coin makers learned that pure metal, particularly gold and silver, was too soft to withstand the harsh conditions from circulation. These metals, as with most coinage metals, were alloyed. The popular alloy of sterling, for example, has a silver content of .925, added to .075 copper for strength and hardness. This alloy proved satisfactory as a coinage composition, to strike, to circulate, to retain its color and its value. Later coin silver was introduced with a greater alloy of 90% silver, 10% copper.

Coins were struck in these alloys through the years, except for occasions when the precious metal content was reduced for political reasons: creating debased compositions. In the 19th century copper nickel was introduced and numerous experiments were made in other minor coinage metals.

Modern Alloy Problems.
The gradual rise of primary metal costs in the 20th century has brought economic pressure to change coin compositions. As mentioned, Great Britain stopped using silver in coins in 1920 (all except Maundy coins). The United States stopped striking silver in circulating coins in 1964 (except for silver coins sold to collectors and bullion coins sold to investors). These changes were brought about by the increase in the market price of silver. Coins struck in alloys without precious metal became a token coinage.

In 1965 U.S. silver coins (of 90% silver) were worth more for their silver content than their face value. The obvious event happened: coins were withdrawn from circulation and melted. Gresham’s law came into effect: coins with least intrinsic value replaced in circulation coins of greater intrinsic value, “bad money drives out good money.” This caused a severe coin shortage and widespread trouble for all small commercial transactions. Other countries confronted similar problems; the problem was worldwide.

U.S. Treasury officials were faced with some difficult decisions. What also influenced the solution were the millions of vending machines and fareboxes that were engineered to accept silver coins (including tests of surface resistivity). What was needed was a lower cost alloy that could still be accepted in all those venting machines. The solution was to strike coins in a clad composition. With a layer of silver, or silver-like metal, on each side of a lower-cost base metal, the total costs of blanks would be less, but this would still meet the requirements of the vending machine industry.

In 1981 a similar situation occurred with the price of copper, effecting the striking of cent coins. Here again the solution was a clad composition of copper coating a zinc base metal. In the United States, cents struck from 1982 forward were of copper clad zinc composition.

(The clad technology also created a new industry – manufacturing the clad strip and supplying this, or blanks cut from the strips, to the mints. It was also a brilliant solution for what could be done with all the skeleton scrap after the blanks were cut out. Copper coated zinc scrap, for example, could be melted, and with little reformulation – addition of virgin copper – poured into ingots of – bronze! Scrap technology must be taken into consideration with every decision of coinage composition.)

In each of these solutions the color and appearance of the prior metal was retained (as well as surface resistivity – necessary for vending machine detectors). It is interesting to speculate what the next major change in coin compositions will require and when this will occur.

Nonmetallic Compositions.
For centuries mint officials have wrestled with the problems of composition of the coins they were required to strike. Metal shortages, fluctuating prices, new technology, wartime metal needs, economic and political factors have all influenced coinage metal needs. Mints have experimented with substitute compositions endlessly. It continues today as substitutes for copper and zinc in cents and perhaps a substitute for a copper-nickel five cent piece, are high priorities as these metal prices have risen beyond the face value of the coins.

In 1868, for example, a Boston firm patented a composition it called Diatite. Unheard of today, it was one of the many unsuccessful coinage compositions, with only two tokens in existence as evidence of this experiment.

In 1865 a dentist and amateur metallurgist, Lewis Feuchtwanger, was more determined. He proposed to the U.S. Mint a nickel-silver alloy as a coinage metal; it contained copper, nickel, zinc, tin, antimony and other metal elements. The Mint wisely refused because of the multiplicity of components (This would have been a scrap technology nightmare.) However, the U.S. Mint later did strike copper-nickel cents, 1856-65, which was not entirely satisfactory, but an altered alloy was satisfactory for five-cent pieces, 1865 onwards. Feuchtwanger designed and issued storecards in his own composition, all struck by Scovill of Waterbury.

In 1942 the U.S. Treasury considered producing cent coins in plastic. In other times the media listed in the adjacent chart below have been considered to replace metal alloys for coins.

But where most nonmetallic compositions are found is in tokens, and to a smaller degree, in medals. Tokens have been struck or fabricated in most all of the materials listed in the chart. Medals, likewise have been made in more than half of these. The experience found among nonmetallic compositions for tokens and medals have given experience to mint officials not to use these compositions for coins. They still wisely use metal for coin compositions.

Handy & Harman Medal

Obverse, reverse and edge of
the Handy & Harman Medal.

Compositions for medals.
Unlike coins, medals and medallic objects have no restrictions on composition; medals are far more democratic. They can be made in any permanent composition. Obviously firms in which their product is a suitable coinage material, may request their medals made in their product material. In 1966 Medallic Art Company created a medal for Handy & Harman, a major supplier of silver and bronze, for their 1967 centennial. The bimetal was struck in bronze with a silver inlay covering half the obverse design (catalog 1966-006).

Before plastics were developed, Bakelite, Vulcanite and hard rubber were materials employed for many products. I remember one medal issued by a firm which manufactured combs in hard rubber, active in the last half of the 19th century.  Obviously its medal was made in hard rubber. The term for this category of medals is called product medal.

Despite the wide variety of metal compositions available for striking medals, the old standard – bronze, silver gold – still are most popular today. This is particular true for award medals with an obvious rank of medals. Three or more classes of awards can be created with additional divisions of medal size and plating, gold-plated silver – vermeil – below solid gold, and above silver.

Bronze, time honored, is even more desirable in that it can be given a patina finish, much like statues. The intent of the firm’s Society of Medalists was that each issue be given a different patina. This became unpractical after the 20th issue.

Numismatic medals.
Numismatists like many different compositions in any individual medal, it provides them with a separate VARIETY.

One of Medallic Art’s first customers, Thomas Elder had the firm strike four or five metal varieties in 1910. Recently, a chemist, Thomas Wilfred, had his New York Numismatic Club Presidents Medal struck in six different metals for his 1983 medal

Coin And Medal Compositions               

A. Metallic

  1. acmonital
  2. albata
  3. alpacca
  4. aluminum
  5. aluminum bronze
  6. argentin
  7. bath metal
  8. brass
  9. bronze
  10. copper
  11. copper nickel (cupro-nickel)
  12. chrom-steel
  13. electrum
  14. german-silver
  15. gold
  16. goldene
  17. iron (ferrous)
  18. lead
  19. manganese
  20. nickel
  21. nickel-brass
  22. nickel-silver
  23. oroide
  24. orichalcum
  25. palladium
  26. pewter
  27. platinum
  28. silver
  29. space metals
  30. sterling
  31. tin
  32. titanium
  33. tombac
  34. type metal
  35. white metal
  36. zinc

B. Plated Metals

  1. bronze gilt
  2. gilding metal
  3. goldplated
  4. rolled gold
  5. sheffield plate
  6. silverplated
  7. vermeil

C. Nonmetallic

  1. bakelite
  2. boxwood
  3. ceramic
  4. glass (crystal)
  5. hard rubber
  6. horn
  7. ivory
  8. leather
  9. plastics
  10. porcelain
  11. soap
  12. steatite (soapstone)
  13. stone
  14. terra-cotta
  15. vulcanite
  16. wax
  17. wood (bois durci)

Some Compositions Terms

Acmonital.  An alloy of stainless steel.
Albata.  Alloy of nickel, copper and zinc; an early name for nickel-silver.
Alpacca.  Onetime trademark for an alloy of copper, nickel and zinc; a form of German-silver or nickel-silver.
Aluminum.  A very light-weight metal in silver-white color.
Aluminum Bronze.  A bronze alloy with five to ten percent aluminum. commercial aluminum bronze formula is 86 copper, 10.5 aluminum and 3.5 iron which is a high strength,
Amalgam.  Any soft metal alloy from which a medallic item is cast or struck; an alloy without specific formulation, as pot metal, which is pliable to some degree.
Anodized Aluminum.  A coating, actually a plating on aluminum which unlike other plating can be done in color.
Argent.  French, silver.
Argentin, Argentine.  Base alloy of tin and antimony, made to resemble silver; a white metal most always silverplated.
Base Metal.  An alloy or metal usually of low value to which plating is applied; or the chief constituent of an alloy, not a precious or noble metal.
Bath Metal.  A brass alloy once used for striking medals. Named after Bath England, it was invented by William Wood (1671-1730) an English ironmaster and owner of copper and tin mines in western England.
Bell Metal.  The bronze alloy for making bells can be used successfully for striking or casting medals.
Brass.  An alloy with the major component of copper, plus moderate zinc or tin content, which is highly ductile and has a yellow hue.
Britannia Metal.  A silver-white alloy of tin, antimony and copper, and often of zinc and bismuth.
Britannia Standard.  A fineness of silver, 958.4 parts per 1000.
Bronze.  An alloy of copper with additional metals of zinc and/or tin in small amount, infrequently with other metals as trace or impurities. Bronze is the world’s most popular alloy for coins and medals, irrespective of how they are made.
CastIron.  A ferrous metal object formed in a mold.
Coin Silver.  A fineness of 900 fine; 9 parts silver to one of alloy, usually copper; silver United States coins have been struck in this fineness from 1837 to 1964.
Copper.  A metal element, the basis for many coinage and medal alloys, making it the most useful metal in the field.
Copper Nickel.  An alloy predominantly of copper, to which is added nickel for hardness and a white color.
Cupro-nickel.  The term for copper nickel in England and France.
Engraver’s Brass.  A copper alloy that is a favorite of engravers because it is so well suited for all types of engraving.
Feuchtwanger Composition.  A three-component alloy employed for several private issue tokens – and proposed for United States coinage by its developer – but never accepted.
Fineness.  The quality or purity of precious metal in numismatic or medallic items. In America fineness is expressed as a decimal part per 1.000, as sterling is .925; in Europe it is expressed as whole parts per 1,000, 925 is sterling.
Fine Silver.  Commercially pure silver, usually .999 fine; silver with no alloy.
German-silver.  A copper alloy of silver-white color because of the presence of nickel and zinc, now called nickel-silver. There is no silver in German-silver or nickel-silver.
GildingMetal.  A base metal, an alloy of copper and zinc.
Gold.  The heavy yellow precious metal, idolized by man for eons, ideal for coins and medals for the highest value and most desirable issues.
Goldene.  A brass alloy resembling gold in which cheap tokens and coins are struck;.
Iron.  The metallic element, silver-white in color, but useful to man for its malleable and ductile qualities.
Karat.  A measure of gold based on 24 parts; 24 being pure gold.
Lead.  A soft bluish gray metal, a metallic element, often used for proving dies in modern times, also a material in which medals have been cast or struck.
Nickel.  A metallic element, of silver-gray color and often alloyed with copper and other metals for a coinage metal.
Nickel-silver.  An alloy of nickel, copper and zinc.
Oreide.  Obsolete form of oroide, the brass alloy.
Oroide.  A brass alloy resembling gold in color and brilliancy widely used in striking low-cost coin-like and token-like medals.
Pewter.  A high tin content white metal alloy, usually very soft and infrequently used for striking medallic items.
Phosphor-bronze.  A bronze alloy with very small amount of phosphor.
Pinchbeck.  An alloy of copper and 10-15% zinc.
Platinum.  A heavy, gray-white precious metal. Platinum has great strength, it never tones or corrodes, but has a very high melting point.
PotMetal.  An alloy without specific formulation but which is made by melting scrap in a pot, hence the name.
RedBrass.  A copper-zinc alloy with less than 15% zinc which has a characteristic bronze red or copper red color.
Silver.  A gray-white precious metal, which because it is highly malleable and coinable is widely used as the composition for coins and medals.
Space Metal.  A new metal alloy formulated in space, outside the gravity restrictions of the earth.
Sterling.  A fineness of silver, 925 parts per 1000 (alloyed with 75 parts copper for hardness).
Spelter.  A zinc alloy, or zinc solder, in which the zinc content is more than half.
Tin.  A very soft white to gray silver-colored metal; an element used in pure state, or alloyed with other metals particularly to form white metal or pewter. 7305-(010)05.4
Tombac.  A copper-zinc alloy.
Type Metal.  A lead alloy containing tin and antimony, it was readily available in letterpress printing shops until the mid-20th century.
Vermeil.  Goldplated silver or silver gilt. Such a composition has the texture, fineness, hardness and smooth finish of silver, but the color of gold.
Wartime Alloy.  Made of a substitute alloy during hostilities.
White Metal.  An alloy with a base of tin, with or without lead, and any of several other medals – copper, antimony, bismuth for the most part.
Yellow Brass.  A copper alloy of high zinc content which has a permanent typical brass golden color.
Zinc.  A silver gray metal that in pure state rapidly corrodes.


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