U.S. coins have changed many times since the Coinage Act of 1792, which adopted the dollar as the standard monetary unit.

Silver dollars have been minted and issued at various times since 1794. Dollar coins were discontinued in 1935, then resumed in 1971 with the introduction of the silverless Eisenhower dollar. The silverless Susan B. Anthony coin, honoring the famed women’s suffrage advocate, replaced the Eisenhower dollar in 1979. A new dollar coin authorized in 1997 replaced the Susan B. Anthony coins in 2000. The new coin depicts Sacagawea, the Native American woman whose presence was essential to the success of the Lewis and Clark expedition. The coin has a copper core clad in an alloy of copper, zinc, manganese, and nickel, which gives the coin a golden color.

Half-dollars virtually disappeared from circulation following the introduction, in 1964, of the Kennedy half-dollar. Despite the fact that huge quantities were produced, the half-dollar remained scarce in general circulation through 1970. Silverless halves first appeared in 1971.

Other coin denominations in common use today are the 25-cent, 10-cent, five-cent, and one-cent pieces, familiarly known as the quarter, dime, nickel, and penny.

The composition of U.S. coins has changed considerably over the past few decades. Because of a growing worldwide silver shortage, the Coinage Act of 1965 authorized a change in the composition of dimes, quarters, and half-dollars, which had been 90 percent silver. Silver was eliminated from the dime and the quarter. The half-dollar’s silver content was reduced to 40 percent and, after 1970, was eliminated altogether.

In 1981 Congress authorized a change in the penny’s composition, abandoning the 95 percent copper and 5 percent zinc alloy used for decades. The one-cent piece is now copper-plated zinc—97.5 percent zinc and 2.5 percent copper. The old and new pennies look virtually identical, but the new coin is about 19 percent lighter.

U.S. coin denominations used in the past were the half-cent, two-cent, three-cent, and 20-cent pieces, as well as a small silver coin called a half-dime. Gold coins in denominations of $1, $2.50 (“Quarter Eagle”), $3, $5 (“Half Eagle”), $10 (“Eagle”), and $20 (“Double Eagle”) were used from 1795 until 1933.

The Mint

The U.S. Mint, which makes all U.S. coins, was established by Congress in 1792 and became an operating bureau of the Treasury Department in 1873.

The Philadelphia Mint has been in continuous operation since 1792. The Denver Mint began its coinage operations in 1906. The West Point, New York, and San Francisco Mints gained official Mint status in 1988. Originally an assay office, the San Francisco Mint is the primary production facility for proof coins. The West Point Mint, once used exclusively as a bullion depository, is now the Mint’s chief producer of gold coins.

U.S. coins typically bear a mint mark showing which mint produced them. Coins minted in Philadelphia bear a P or no mint mark; those minted in Denver, a D; in San Francisco, an S; and in West Point, a W. Although the Coinage Act of 1965 specified that no mint marks would be used for five years, Congress authorized in late 1967 that mint marks be resumed. The marks reappeared on regular coinage in 1968.

Several branch mints are no longer in operation. These mints were located in Carson City, Nevada (mint mark, CC); Charlotte, North Carolina (C); Dahlonega, Georgia (D); and New Orleans, Louisiana (O).


The Director of the Mint selects designs for U.S. coins with the approval of the Secretary of the Treasury, although Congress may prescribe a coin design. A design may not be changed more often than every 25 years unless Congress determines otherwise.

Emblems All of the U.S. coins currently minted portray past U.S. Presidents. They are the Lincoln one-cent piece, adopted in 1909; the 25-cent piece portraying Washington, first minted in 1932; the five-cent piece honoring Jefferson, adopted in 1938; the Franklin D. Roosevelt dime, introduced in 1946; and the Kennedy half-dollar, which appeared in 1964.

The 50 States Quarters Program Act of 1997 provides for the redesign of the reverse side of quarters to depict emblems of each of the 50 states. Each year from 1999 through 2008, coins commemorating five states, with designs created by the states, will be issued in the order in which the states signed the Constitution or joined the Union. These quarters will be in general circulation, but the Mint will also sell sets of collector edition proof, uncirculated, and silver proof coins.

“In God We Trust” The phrase was first used on the U.S. two-cent coin in 1864. It appeared on the nickel, quarter, half-dollar, and silver dollar and on the $5, $10, and $20 gold pieces in 1866, on the penny in 1909, and on the dime in 1916. Dropped from the nickel in 1883, the phrase reappeared on the nickel in 1938. All U.S. coins now issued bear the motto.

The Minting Process

The first step in minting coins is the production of strips of metal in the proper thickness. (The U.S. Mint buys these strips, for all coins except pennies, from commercial suppliers.) Strips for pennies are zinc. Strips for nickels are an alloy of 75 percent copper and 25 percent nickel. Clad dimes, quarters, half-dollars, and dollars are produced from three layers of metal fused together; the outer layers are the same alloy used for nickels, and the core is copper.

The metal strips are fed into blanking presses, which cut round blanks (planchets) the approximate size of the finished coin. (The blanks for pennies, made of zinc, are coated with copper before going on to the next step. Commercial companies provide the planchets for pennies to the Mint.) The blanks are run through annealing furnaces to soften them and then through tumbling barrels, rotating cylinders that contain chemical solutions to clean and burnish the metal. Next, the blanks are washed and put into drying machines. Then the blanks go through milling or “upsetting” machines, which produce the raised (upset) rim.

Blanks next proceed to the stamping or coining press. The blank is held in place by a ring, or collar, as it is struck under tremendous pressure. Pennies require about 40 tons of pressure, and the larger coins require proportionately more. Upper and lower dies stamp the design on both sides of the coin at the same time. Grooves inside the ring holding the blank form the “reeding” or ridges on the rim of finished coins, except for pennies and nickels, which have smooth rims.

Commemorative Coins

Coins to commemorate American people, places, events, and institutions are authorized by special acts of Congress and manufactured in limited quantities. Commemorative coins, which may be gold, silver, or clad, usually sell at a premium, so they seldom circulate as regular coin.

Legislation specifies that commemorative coin programs must operate at no net cost to taxpayers. Surcharges raised from the sale of commemorative coins are designated for a specific purpose or for reducing the national debt.

The first commemorative coin was minted in 1892 to help finance the World’s Columbian Exposition in Chicago. Since that time many other commemorative coins have been issued.

Recent commemorative coins have included 1996 Centennial Olympic coins as well as coins honoring Franklin Delano Roosevelt and Jackie Robinson in 1997; Robert F. Kennedy and Crispus Attucks, an African-American Revolutionary War patriot, in 1998; and Dolley Madison in 1999.

Used by permission of the Federal Reserve Bank of Atlanta.