Challenge coins, introduced during World War I as a way of encouraging troops, continues today in all branches of the military. In addition, schools and universities, businesses, and charitable organizations utilize challenge coins to encourage team unity and tradition. Producing challenge coins requires several types of equipment, and involves a detailed process.
Producers of challenge coins decide on several different types of metals for specific coins, based on each metal's unique color, luster and hardness. Copper, nickel, gold, silver and platinum highlight the typical metals used.
Die Stamp Equipment
Two hardened steel dies stamp the design selected on the metal for the coins. One die is in a recess shape, forming the shape of metal for the coin. The other die, or the male die, presses into the recessed, or female die. Designs on both dies are impressed into the metal.
Melt Process Equipment
Challenge coin makers melt the metal in an oven, and pour the metal into billets, which have a small rectangular opening, where the cooling metal is pressed through into long thin strips. A hand roller or machine roller then further thins the strips of metal. A micrometer tool is used to measure the precise thickness of the metal strip.
A blanking press punches out blank discs of the metal from the sheet. Each disc goes through a vibrating finishing machine, which through hundreds of tiny ball bearings, mixed with soap and water, smooths out rough edges and cleans each of the coin blanks.
A minting press stamps the coin blanks, which are inserted in a round collar between the top and bottom dies. The pressure from each stamp of the dies leaves the finished design imprint on both sides of each coin.
Finishing Artwork Equipment
Some coins require color artwork. A special engraving instrument produces precision color on whatever parts of the coin chosen.