The United States Mint has minted over 20 different kinds of coins, of many different sizes. Often, it is difficult for people to get a grasp of what much of the historical coinage looked like, at least in relation to modern circulating coins. This chart shows all of the coin types, and their diameters, grouped by coins of similar size and by general composition.
Seven distinct types of coin composition have been used over the past 200 years: three base coin alloys, two silver alloys, gold, and in recent years, platinum and palladium. The base metal coins were generally alloys of copper (for 2 cent coins and lower), and copper/nickel (for 3 and 5 cent coins). Copper/nickel composition is also used for all modern "silver" coins.
+ US Coin Sizes and Composition Steel Alloy Copper Copper Alloy Silver Alloy Silver Gold PlatinumPalladium Three Cent14 mm0.8 g0.750 fine1851–185314 mm0.75 g0.900 fine1854–1873 Half Dime15.5 mm1.24 g1794–1873 Dollar15 mm1.67 gr1849–1889 $5 American Gold Eagle16.5 mm3.11 g1986–present $10 American Platinum Eagle16.5 mm3.11 g1997–present Three Cent17.9 mm1.94 g1865-1889 Dime (Clad)17.91 mm2.268 g1965–present Dime17.9 mm2.5 g1796–1964 $2.50 Gold Quarter Eagle18 mm4.2 g1796–1929 Small Cent19.05 mm2.5 g1943Small Cent19.05 mm3.11 g1864-1982Small Cent19.05 mm4.67 g1856-18642.5 g1982–2025Three Dollar20.5 mm5.01 g1853–1876Nickel21.21 mm5 g1866–present Nickel21.21 mm5 g1942–1945 Twenty Cent22 mm 5 g1875–1878 $5 Half Eagle21.6 mm8.36 g1795–1929 $10 American Gold Eagle22 mm7.78 g1986–present $25 American Platinum Eagle22 mm7.78 g1997–present Half Cent23.5 mm6.74 g1795–1857 Two Cent23 mm6.22 g1864-1873Quarter (Clad)24.26 mm5.67 g1965–present Quarter (40% Ag)24.3 mm5.75 g1976(S) Quarter24.3 mm6.25 g1796–1964Dollar26.49 mm8.1 g1979–Present $10 Eagle27 mm17.5 g1795–1933 $25 American Gold Eagle27 mm17.5 g1986–present $50 American Platinum Eagle27 mm15.6 g1997–presentLarge Cent28 mm10.89 g1793–1857Half Dollar (Clad)30.61 mm11.34 g1971–present Half Dollar (40% Ag)30.6 mm11.5 g1965–1970, 1976(S) Half Dollar30.6 mm12.5 g1796–1964 $50 American Gold Eagle32.7 mm31.1 g1986–present $100 American Platinum Eagle32.7 mm31.1 g1997–present $20 Double Eagle34 mm35 g1849–1933$25 American Palladium Eagle34.036 mm31.120 g2017–presentDollar (Clad)38.1 mm22.68 g1971–1978 Dollar (40% Ag)38.1 mm24.59 g1971(S)-1976(S) Dollar38.1 mm26.73 g1794–1935 $1 American Silver Eagle40.6 mm31.1 g1986–present
+ Representative images of US coin sizes Steel Alloy Copper Copper Alloy Silver Alloy Silver Gold PlatinumPalladium
Notes on the tables:
Images are close to actual size on a 92-dpi monitor. Clad Half Dollars, Silver Half Dollars and Dollars, and Gold Half Eagles and Eagles are still regularly minted as commemorative coins. Dimes, quarters and half dollars are also struck in 90% silver for special annual collector's sets. The silver-colored Susan B. Anthony dollar was replaced with gold-colored Sacagawea dollar in 2000 and Presidential Dollars 2007-2016; though the composition changed, the coin's size and weight remain the same. Some variances in coin size and weight occurred over time, especially as the value of silver varied. In particular, many silver coins changed in the 1870s. Evans, George Greenlief. Illustrated History of the United States Mint ... American Coinage ...: With Biographical Sketches of the Mint Officers from Its Foundation to the Present Time; to which are Added a Glossary of Mint Terms and the Latest Official Tables .... United States: Geo. G. Evans, Pub., 1893. The figures cited in the tables are representative of the series, and are generally the latest, or most common, figures for a given coin type.
The largest coin ever minted by the US Mint was the 2019 Apollo 50th anniversary 5ounce silver dollar, weighing 155.517 grams, and 76.2 mm in diameter.
References