What Is the Mint Mark on a Coin and Why Does It Matter?

A mint mark is a small letter or symbol stamped onto a coin, identifying the specific United States Mint facility where it was produced.

What Mint Marks Indicate

Each letter or symbol on a coin corresponds to a specific United States Mint facility. The “P” mint mark signifies coins produced at the Philadelphia Mint, one of the oldest and largest mints. Coins bearing a “D” mint mark originate from the Denver Mint, a significant producer of circulating coinage. The “S” mint mark denotes coins struck at the San Francisco Mint, known for producing proof and commemorative coins. A “W” mint mark indicates production at the West Point Mint, which specializes in bullion and commemorative issues.

Beyond these active facilities, historical mint marks also exist, representing former U.S. Mint branches. The “C” for Charlotte and “D” for Dahlonega were used on gold coins produced by these southern mints, which operated from 1838 to 1861. Coins bearing an “O” mint mark hail from the New Orleans Mint, active during various periods between 1838 and 1909. The “CC” mint mark identifies coins from the Carson City Mint, which operated from 1870 to 1893, primarily minting silver coins.

Locating Mint Marks on Coins

The precise location of a mint mark varies depending on the coin’s denomination, series, and year of mintage. Generally, older U.S. coins frequently feature the mint mark on the reverse, or tails side. Since 1968, however, the U.S. Mint began placing mint marks on the obverse, or heads side, for many denominations.

For instance, on a Lincoln Cent, the mint mark is typically found on the obverse, just below the date. Roosevelt Dimes minted after 1968 have their mint mark above the date on the obverse, while earlier issues (1946-1964) show it on the reverse. Washington Quarters from 1968 onward display the mint mark on the obverse. Before 1964, the mint mark for quarters was located on the reverse. Kennedy Half Dollars from 1968 to the present have the mint mark on the obverse, above the date, whereas the 1964 issues placed it on the reverse.

Variations in Mint Marks

Not all U.S. coins feature a visible mint mark, particularly those produced at the Philadelphia Mint for much of its history. Until recently, coins struck in Philadelphia often did not carry a mint mark, with the absence indicating their origin. This practice changed over time, with the “P” mint mark first appearing on circulating five-cent coins during World War II (1942-1945) to denote their altered metallic composition. The “P” mint mark then became a regular feature on most Philadelphia-minted denominations starting in 1980, with the notable exception of the Lincoln Cent until 2017.

The style, size, and exact positioning of mint marks have evolved across different coin series and eras. During a period between 1965 and 1967, mint marks were temporarily omitted from all circulating coins to discourage collecting.

Importance of Mint Marks

Mint marks are important, especially within the field of numismatics, the study and collection of currency. They help determine a coin’s rarity, historical context, and market value. Coins produced at mints with lower mintage numbers for a particular year or series tend to be more rare and, consequently, more valuable to collectors.

For example, coins from the Carson City Mint (“CC”) are highly sought after due to their limited production runs during the mint’s operational period. Certain coins from the West Point Mint (“W”), particularly proof or special issues, can command higher values because of their perceived quality and lower quantities. Mint marks also help collectors complete sets, as a comprehensive collection often includes examples from every mint that produced a specific coin type.