Mintmark: A letter or other mark on a coin denoting the mint that manufactured the coin.
US coins are avidly collected by date and mintmark, and the presence or absence of a mintmark can mean huge differences in the value of a coin. The 1927 Double Eagle is a relatively humble coin - or at least as humble as a twenty dollar gold piece can be. The 1927-S is quite a rare coin, with even the worst specimen likely to bring $5,000 and up at auction. However, the 1927-D is a tremendous rarity, bringing six figure prices whenever it is offered. What's the difference between these three coins? The mintmark.
Any collector needs to be able to spot the mintmark both on a coin and within the coin's description. The latter is easy - the term "1927-D" means that the coin is dated 1927 and carries a 'D' mintmark. If the date of a US coin is written without a mintmark, it means that the coin has no mintmark and was (usually) minted in Philadelphia. Coins without mintmarks made in Philadelphia are sometimes referred to as, for example, 1927-P, even though there may be no mintmark on the coin. Most exceptions to the rule that US coins without mintmarks are from Philadelphia have occurred in the last 40 years.
Mintmarks that appear on US coins include:
C: Charlotte (Gold only, 1838-1861)
CC: Carson City (1870-1893)
D: Dahlonega, Georgia (Gold only, 1838-1861)
D: Denver (1906 to date; easily distinguishable from Dahlonega because of the different timeframes in which the mints operated)
O: New Orleans (1838-1909)
P: Philadelphia (Silver "Nickels" 1942-45; Dollar coins 1979 to date; other coins except cents 1980 to date. Although the Philadelphia mint has been operating continuously since 1793, most Philadelphia coins do not have a mintmark)
S: San Francisco (1854 to date. Now mints collector coins only. The last circulating coin to bear an 'S' mintmark was the 1980-S SBA Dollar)
W: West Point (1983 to date; collector coins only)
If you consider US coins to include issues struck for the Philippines both under Sovereignty of the US and as a Commonwealth, you would have to add the 'M' mintmark for the Manila mint to the above list.
For the most part, mintmarks on circulating coins appear on the reverse of the coin if the coin was dated 1964 or earlier. No mintmarks appeared on any US coins dated 1965-67, but in 1968, the four circulating coins that had not already had an obverse mintmark had the mintmark moved to the obverse. A good rule of thumb when searching for a mintmark is to look near the date or at the bottom of the reverse, often below the wreath or the eagle.
Specific locations of mintmarks on US circulating coins are as follows:
Half Cent: None
Large Cent: None
Flying Eagle Cent: None
Indian Head Cent: Below the wreath on the reverse; 1908-S and 1909-S only
Lincoln Cents: Below the date. Philadelphia mint coins in this series minted today still do not carry a mintmark; these are the only US circulating coins that bear that distinction.
Two Cent Pieces: None
Silver Three Cent Pieces: To the right of the 'C' on the reverse; 1851-O only
Nickel Three Cent Pieces: None
Shield Nickel: None
Liberty Nickel: Below the dot to the left of "CENTS" on the reverse; 1912-dated coins only
Buffalo Nickel: Below "FIVE CENTS" on the reverse. The 'F' below the date (at least when the date is visible) is the initial of the designer, James Earle Fraser.
Jefferson Nickel: Copper-Nickel pieces dated 1938-42 and 1946-64: to the right of Monticello on the reverse. Silver pieces dated 1942-45: a large mintmark above Monticello on the reverse. 1968-2004: Below (clockwise from) the date. 2005 Redesign: Below the script "Liberty" on the obverse.
Early and Bust Half Dimes: None
Seated Liberty Half Dime: Within the wreath below "HALF DIME" on the reverse 1838-1859, 1870-72. Below the wreath on the reverse 1860-69, 1872-73.
Early and Bust Dimes: None
Seated Liberty Dime: Within the wreath below "ONE DIME" on the reverse 1838-1860, part of 1875. Below the wreath on the reverse 1860-91.
Barber Dime: Below the wreath on the reverse
Mercury Dime: To the right of the word "ONE" on the reverse. The 'W' in the right obverse field is actually the AW monogram of the designer, Adolph A. Weinman.
Roosevelt Dime: 1946-64: To the left of the bottom of the torch on the reverse. 1968 to date: Above the date.
Twenty Cent Piece: Below the eagle on the reverse
Early and Bust Quarters: None
Seated Liberty Quarter: Below the eagle on the reverse
Barber Quarter: Below the eagle on the reverse, but often a little skew due to lack of room.
Liberty Standing Quarter: Above and to the left of the date, immediately to the right of the bottom star on Liberty's left (facing) side. The incuse 'M' above and to the right of the date (if visible) and immediately to the right of the bottom star on Liberty's right (facing) side is the initial of the coin's designer, Hermon MacNeil.
Washington Quarter: 1932-64: Below the wreath on the reverse. 1968 to date, including Statehood Quarters: To the right of Washington's ponytail on the obverse - which in the case of Statehood quarters is not the dated side of the coin.
Early Half Dollar: None
Bust Half Dollar: Above the date on the 1838-O and 1839-O Reeded Edge coins only. The former is a legendary rarity.
Seated Liberty Half Dollar: Below the eagle on the reverse
Barber Half Dollar: Below the eagle on the reverse
Walking Liberty Half Dollar: 1916-17: Below "IN GOD WE TRUST" on the obverse. 1917-47: To the left of "HALF DOLLAR" on the reverse.
Franklin Half Dollar: Above the Liberty Bell and below the 'E' in "STATES" on the reverse.
Kennedy Half Dollar: 1964: To the left of the olive branch on the reverse. 1968 to date: Above the date.
Early and Gobrecht Silver Dollars: None
Seated Liberty Dollar: Below the eagle on the reverse
Trade Dollar: Above the 'D' in DOLLAR on the reverse
Morgan Dollar: Above the "DO" in DOLLAR on the reverse
Peace Dollar: On the reverse below "ONE" and above the eagle's tail
Eisenhower Dollar: Above the '7' in the date
Susan B. Anthony Dollar: To the left of Ms. Anthony on the obverse
Sacagawea Dollar: Below the date
Gold Dollar: Below the wreath on the dated side of the coin
Early Quarter Eagles: None
Classic Quarter Eagle: Above the date, 1838-39 only
Liberty Quarter Eagle: Below the eagle on the reverse; in fact, most mintmarks in this series are partially merged into the eagle due to space limitations.
Indian Quarter Eagle: To the left of the arrows (eagle's perch) on the reverse.
Three Dollar Gold: Below the wreath on the dated side of the coin
Early Half Eagles: None
Classic Half Eagle: Above the date, 1838 only
Liberty Half Eagle: 1839: Above the date. 1840-1907: Below the eagle on the reverse.
Indian Half Eagle: To the left of the arrows (eagle's perch) on the reverse.
Early Eagle: None
Liberty Eagle: Below the eagle on the reverse
Indian Eagle: 1908-D coins with no motto: Above (clockwise from) the left end of the branch on the reverse. All others: to the left of the arrows (eagle's perch) on the reverse.
Liberty Double Eagle: Below the eagle on the reverse.
Saint-Gaudens Double Eagle: Above the date
Of course, mintmarks also appear on US commemorative and bullion coins, but the coins, let alone the mintmark locations, are far too varied to go into here.
Although collectors of US coins are used to mintmarks being letters, mintmarks can be virtually anything that would identify the place of the coin's manufacture. The first coins were issued by city-states and did not necessarily need mintmarks, as anything that would identify the issuer would suffice. However, Roman Republican coins often bore the name of the moneyer (this practice continues to the present day in some places), and the Roman Empire, in an attempt at uniformity, started to use mintmarks in the middle of the third century.
These marks took the form of a combination of letters - the first part to indicate that the coin was in fact money (later to indicate the metallic content - silver or gold), the second to indicate where the coin was struck, and the third to indicate which workshop within the mint struck the coin. Unfortunately, the order in which these three parts appeared could vary, and sometimes not all of the three parts would appear, which results in the fact that Roman coins can have an immense number of different mintmarks. The point of the mintmark was keep track of the people manufacturing the money, in that coins of improper weight and fineness could be traced back to the responsible party, who would likely regret having been traced for the rest of their often very short lives.
Medieval mints used a dizzying assortment of marks, often small pictures or symbols. A glance at Coincraft's Standard Catalogue of English and UK Coins 1066 to Date, for example, shows that eleven pages are dedicated to enumerating and picturing the mintmarks that appear on British coinage between 1334 and 1662. Fortunately, the bulk of British coinage made during this time consisted of pennies, most of which also bore the name of either the minting city or the moneyer.
Mintmarks on more modern world coins may be letters, or monograms, with the familiar Mexican M
o mintmark, signifying Mexico City, being an example of the latter. Even today mintmarks may still be symbols, such as the heart that has long been the mintmark of the Copenhagen mint. Today, with the advent of industrialized mints that are able to handle huge coinage loads and the elimination of circulating precious metal coinage, there are fewer mints, often only one per country. This renders mintmarks less necessary, and many mints do not use them.