Mint marks are tiny letter referring to the locality where the minting of coins took place. The position of the mint mark can typically be found on the back side of most coins that were minted before 1965, except for the cents and at the front after the year 1967.

Coins of every U.S. Mint branch are recognized by their mint marks. These coin marks date back to ancient times in Rome and Greece.

The “Director of the Mint”, through “Act of March 3, 1835” sets rules to classify and distinguish the coins released from every “U.S. Mint branch.” This core management made accurate standards and patterns of production as well as responsible coinage.

Coins that arrived at the “Philadelphia Mint” much earlier than the year 1979 have no mint marks. So it was in that year that the dollar was marked with the letter P and other denominations had that same mark thereafter.

All Dies for U.S. coins are produced at the “Philadelphia Mint” and prior to shipping the coins to their mint branch, coins are marked first with the correct and designated markings. The precise size and positioning of the coin’s mint mark can vary slightly. This is influenced by how deep the punch was impressed and where.

As such mint marks are an important characteristic of a coin. From mint marks collectors can determine the value of a coin, along with the coin’s date and condition to determine the coin’s value.

Defining the Mint from which a given coin was minted at is tremendously important as well to arrive at a value for the coin. The coin could have been minted in huge quantities from one Mint location and in minute quantities from a different Mint.

The Process of Minting:


1. The making of metal strips in the correct thickness. Zinc-strips are used for pennies, alloy strips composed of nickel (25%) and nickel (75%) for nickels and dollars, half-dollars, dimes, half-dimes are fabricated from a fusion of three coatings of metals; the external layer are alloys and the center is copper.
2. These strips of metal are then put into “blanking presses” that are responsible for cutting “round blanks,” approximately the dimension of the “done” coin.
3. The banks are then softened by running them through an anneal furnace, through barrels tumbling and lastly through revolving cylinders containing chemical mixtures to burnish and clean the metal.
4. The blanks are then washed up and placed into a drying device, then in “upsetting” machines, which produces raised rims.
5. The final stage is the “coining press.” Each blank is clasped into position by a collar or ring as it is being struck or hit under great pressure. Pennies need 40 tons or so of pressure, while much bigger coins require even more pressure. The “upper and lower dies” are stamped simultaneously on the two sides of each coin.

The Design:

The Director of the Mint chooses the design and patterns for United States coins that is then approved by the Secretary of the Treasury. Congress can recommend and suggest coins designs. The design can not be changed until every twenty-five years of gap unless otherwise determined by Congress.

All emblems of United States coins currently minted represent previous presidents of the U.S. President Lincoln is on the one-cent adopted in the year 1909. George Washington is on the 25 cent coin that was first minted in 1932. Thomas Jefferson is on the five cent coin first minted in 1946. John F. Kennedy is on the half-dollar that was minted in 1964.

The 50 Quarters Program started by the Act of 1997 redesigned the reverse side of quarters to show each of the fifty states emblems. Every year starting in 1999 through 2008, the quarters would have designs that were made in each state. Each quarter were issued in the sequence or manner that each state joined the United States.

The phrase “In God We Trust” was first used in 1864, on a U.S. two cent piece. It was then seen on the quarter, nickel, half-dollar, silver dollar and other coin denominations. Today all U.S. coins carry this motto despite some attempts to have it removed. But that is another story.