The United States Mint has been in operation since 1792. In the years since its founding, the Mint has produced coins for the United States (as well as occasional times minting coins for other countries). At first, the Mint operated out of its Philadelphia facility. It has since expanded over the years, establishing locations in Denver, San Francisco, Carson City, New Orleans, and other places. At present, the U.S. Mint makes coins at four locations: Philadelphia, Denver, San Francisco, and West Point.

Of the four currently operating Mint facilities, only two create coins intended for circulation: Philadelphia and Denver. San Francisco once did so, though it no longer does. Both the Mints at San Francisco and West Point have produced supplementary coinage bearing no Mint Mark identifying the source of the coins.

I’ll be sharing with you examples of all four Mint Marks currently in use, with photos taken from relatively recent additions to my collection.

So what is a Mint Mark? When the United States Mint was founded, there was only the Philadelphia Mint. As such there was no need to identify the source on the coin. Coins Minted at Philadelphia bore no Mint Mark at all.

Mint Marks today are located on the obverse (front) of the coin, near the date in all cases except that of the currently minted dollar coins, where they are found on the edge of the coin. Prior to 1964, Mint Marks were primarily found on the reverse of the coin (except for in the case of the Lincoln cent and on certain gold coin designs), near the bottom of the main design.

The first time the Mint put a P Mint Mark on a coin for Philadelphia was during World War II. In order to designate the special composition of nickels struck during the war, the Mint enlarged the Mint Mark and put it over the dome of Monticello, using a large P to designate coins from Philadelphia, a D for those from Denver, and an S for those from San Francisco.


A War nickel from San Francisco.

After the war, the P was dropped again, not to return until the Susan B. Anthony dollar coin was struck in 1979.


A 1965 Kennedy Half Dollar.

The following year, all remaining coins save the Lincoln cent received the P Mint Mark. The Lincoln cent is the only coin struck by the Mint today which may bear no Mint Mark. Philadelphia mints the most diverse selection of coins of the four Mint facilities, making a variety of coins both for circulation and with special finishes.


A Philadelphia Reverse Proof Dime from this year’s March of Dimes commemorative set.

The U.S. Mint at Denver was originally founded as an assay office in 1863, where the purity of metals could be tested prior to being minted into coins. It wouldn’t be until 1904 that the Denver Assay Office was granted official status as a mint, striking its first official coins for the United States in 1906.


The Denver and Philadelphia mints produce all of the coins currently meant for circulation in the United States. If you take a look at the change in your pocket, the odds are pretty good that all of it was produced at one of these two mints.

A Lincoln cent minted in Denver.

The Mint Mark for Denver is a D, a mark originally used by the defunct mint in Dahlonega, Georgia, which was established to coin the gold discovered in the Georgia Gold Rush. Denver produces coins almost exclusively for circulation, with occasional forays into coins with special finishes.


Philadelphia and Denver produce our circulating coinage, but San Francisco and West Point now produce coins primarily for collectors.

The San Francisco Mint was founded directly as a branch mint, opening in 1854 to handle the demand for coinage following the California Gold Rush. San Francisco Minted coins in its original facility until 1937, when it moved to its current location.


The San Francisco Mint.

The San Francisco Mint mostly puts its mark on coins made for the sake of collectors today. Proof coins are their most notable product these days, a job that originally belonged exclusively to the Philadelphia Mint. San Francisco’s last marked coins minted for general circulation were Lincoln cents and Jefferson nickels produced from 1968-1970, and Susan B. Anthony dollars produced in 1979 and 1980.


A 1970-S Lincoln cent. Apologies for the blurriness.

San Francisco’s production has been varied in composition and design, including both standard and special issues. West Point, however, is unique among the current branches of the U.S. Mint in that it has only once minted a coin out of base metal that bears its Mint Mark. The 1996-W dime, released only in Uncirculated sets produced in that year, marked the 50th anniversary of the Roosevelt Dime design.


The 2015-W Proof silver Dime and Dollar coins from the March of Dimes commemorative set.

West Point’s production primarily consists of gold, silver, and platinum bullion coins as well as special commemorative issues. Most recently, for instance, the West Point Mint produced two of the three coins for the 2015 March of Dimes commemorative set, contributing a 2015-W silver Proof Dime and a 2015-W Proof commemorative silver dollar (Philadelphia contributed the third coin, a 2015-P silver Reverse Proof Dime).


The 2015 March of Dimes commemorative set in full. Kinja is to blame for orientation - it shows up correctly in the editor.

Of the four branches of the U.S. Mint, most people will only ever see coins bearing two of their marks, three should they be lucky enough to find some of the rare circulating coins minted in San Francisco. As commerce becomes more electronically based, it is unlikely that the U.S. Mint will expand into other branches in the future; these four probably represent the only branches that will continue on in our lifetime. New Orleans, Charlotte, Dahlonega, Carson City - those branches will never be recommissioned. There are interesting stories to share about them, but those are stories for another day.