Facts About U.S. Coins

American coins have a long history filled with interesting facts.

Coins have been a staple of developed economies since the early days of ancient Chinese and Greek civilizations. The United States has a highly developed and complex coin production system involving engravers, mints and amalgams of various types and percentages of metal. The history of U.S. coins and their changes is equally as interesting.

Mints

All U.S. coins are minted by the Department of the Treasury.

All circulating U.S. coins are manufactured by the U.S. Department of the Treasury in the nation's mints. U.S. mints are in Philadelphia; Washington, D.C.; West Point, New York; Fort Knox, Kentucky; Denver; and San Francisco. Annual production of circulating coins, according to the U.S. Mint's website, fluctuates between 11 million and 20 million coins. Often a letter will appear under the date on the coin, indicating where it was minted. Philadelphia coins sometimes bear a "P," though oftentimes are not marked.

Variations

The Indian head, or buffalo, nickel, was in production during the Great Depression. The front of the coin bore a composite portrait of the Native American chiefs Big Tree, Two Moons and Iron Tail, while the reverse side was a rendering of the famous Central Park Zoo buffalo (technically, American Bison) Black Diamond. The coins went out of circulation in 1938. Other variations on contemporary coins are the Lincoln wheat cent, a penny with Lincoln on the front and parenthetically shaped wheat plants on the back (circulation 1909-1959) and the Mercury dime, which featured a portrait of the Roman god Mercury (1916-1945).

World War II

In 1943, at the height of U.S. involvement in World War II, the government experimented with alternate materials in the production of coins in order to conserve certain metals expressly for the war effort. The most notable example of this movement was the steel penny. In production for only a year, the coin looks much like a Lincoln wheat cent apart from its silver appearance. The coin had a number of problems, from its tendency to rust quickly to its being confiscated by vending machines engineered to catch steel slugs.

Engravers

American coin designs are created by government-employed sculptors and engravers.

The U.S. Mint employs a handful of sculptors and engravers who are charged with the production of designs for all U.S. coins and medals. These engravers and sculptors work at the Philadelphia mint, the only one of the nation's six coin production facilities that engraves coin designs. Once a design is finalized, a plaster mold is created. A machine is used to create a coin-sized model of the mold, from which imperfections are removed by the engravers. This model is then used to press coins.

Composition

U.S. coins are composed of various metals, such as nickel and copper.

Silver U.S. coins--dimes, nickels, quarters and half dollars--have very similar compositions. All are some combination of nickel and copper; the nickel has the highest percentage of its namesake metal at 25 percent. Dimes, quarters and half dollars are 8.33 percent nickel. Pennies are copper-plated zinc; the bronze of copper gives the coins their unique color. Dollar coins contain a larger variety of metals. The presidential and native American $1 coins are 88.5 percent copper, 6 percent zinc, 3.5 percent magnesium and 2 percent nickel.

References

• The United States Mint: Sculptors and Engravers
• The United States Treasury: Coin Composition
• Absolute Astronomy: Indian Head Nickel
• Collectors Weekly: Lincoln Cent
• Mercury Dime Information Resource