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Iron.  The metallic element, silver-white in color, but useful to man for its malleable and ductile qualities. The numismatic and medallic field could not exist without iron and its high-carbon attendant, steel. The first dies for striking coins and medals were made of iron, as are, of course, all those produced today. Presses are mostly iron, tools are made of steel. (Coins were once made of iron – for the Peloponneus and some wartime alloy – but it is not generally a coinage alloy, it ranks low in coinability because of its difficulty to strike.) However, the importance of iron cannot be understated in the coin and medal field today.  See dies and diemaking, presses.

While only a miniscule number of medallic objects are currently made of ferrous material, cast iron has long been used for casting plaques and patterns in the medallic field. For the items made in the 19th century, iron was considered a satisfactory media, particularly for small plaques and large medallions. The obvious test for iron composition for any object – decoration, medallic, or jewelry – is a magnet. All such objects react to a magnet.

Iron dies.  The very first dies were made of iron, and this has continued for 2600

years. While some forays have been made with copper dies, striking has proved only successful with iron, and later steel. It was the English manufacturer Benjamin Huntsman who invented a method of making crucible steel (1756) that proved beneficial. After studying all iron available for dies, it was Huntsman's steel that Matthew Boulton choose for his Soho Mint. The Huntsman firm supplied steel to mints for making dies for nearly 200 years (until 1950).

Iron coins.   Coins struck in stainless steel, called acmonital. Stainless is very

difficult to strike but has been used for coinage compositions. The low coinability is offset by its lower cost. Acmonital coins are, of course, magnetic and this does provide some difficulty in vending machines. Italy was the first country to use acmonital metal for coins and they have been very successful in striking this composition.

Berlin iron.  The Germans had been using iron for jewelry and medallic items since 1804. The famed Iron Cross, founded in 1813 (and renewed in 1870, 1895, 1914 and 1939), was made in iron both for its name and the rank of its award. The Royal Berlin Factory cast decorative objects in iron, often in delicate design with openwork. When Napoleon captured Berlin in the Napoleonic Wars, he ordered the molds of iron jewelry and decorations taken to Paris in 1806 where they were made for a short time.

In 1813 Berlin factories resumed making iron objects, changed the motifs from an austere design of the Napoleonic period, to more naturalistic style. Gothic revival style flared 1830-50. A few American pieces were made of Berlin iron (see illustration).

Iron medals. In the 20th century, heroes were honored with large iron medals by several medallic firms. Famed German satirist Karl Goetz (1875-1950) made many of his productions in iron, often exclusively in iron, others in both bronze and iron. See CAST MEDALS.

Iron patina.  Most German iron objects are not susceptible to rusting. They are often found in a black patina and rust free, of both 19th and 20th century items. Perhaps a study should be made as to the protection and patina they employed with all iron medals.

Iron rust.  Untreated iron oxidizes in the presence of moisture. Dies are

particularly vulnerable. High portions of the die (usually the field or background) are most susceptible, rust pits form here more than any other in a die. Rust pits show up in any piece struck from a rusted die as raised lumps or bosses.  See rusted dies, corrosion.

excerpted with permission from

An Encyclopedia of Coin and Medal Technology

For Artists, Makers, Collectors and Curators


Roger W. Burdette, Editor

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