The weight of any coin depends upon three factors: diameter, thickness, and material composition. As such, coins made out of different materials, having different thicknesses, and different diameters will weigh different amounts. Mints from around the world have used a variety of different materials to manufacture coins ranging from precious metals, such as gold and silver, to low-cost steel that sells for pennies a pound.
The composition of United States coinage is determined by laws passed by the United States Congress and approved by the President. The Coinage Act of April 2, 1792, established the denominations and specifications that the Treasury Department could direct the United States Mint to manufacture. Congress must approve any changes to the diameter, weight, and composition of the coins.
Although the United States is one of the few nations in the world that has not officially adopted the metric system for commerce, all coin specifications for United States coinage is given in millimeters for diameter and grams for weight.
How Much Does a Penny Weigh?
The United States Mint currently manufactures one-cent coins that consist of a core of 99.2 percent zinc and 0.8 percent copper plated with less than 0.003 inches of pure copper. It is 19.05 millimeters in diameter and weighs 2.5 grams with a tolerance of ± 0.1 grams.
Pennies dated from 1864 until 1982 were made with 95 percent copper and 5 percent zinc. These coins weighed 3.11 grams with a tolerance of ± 0.13 grams. In 1982, the mint produced half of the pennies with the solid copper composition and half of the pennies with the copper-plated zinc composition.
In 1943, Congress dictated that the United States Mint changed the composition of the penny to a core of pure steel plated with zinc. This change in composition was intended to save copper for the manufacturing of munitions to be used in World War II. These steel pennies weigh 2.689 grams with a tolerance of ± 0.13 grams. These steel cents quickly started to rust and deteriorated. In 1944, Congress reversed its decision, and the composition returned to the copper and zinc alloy.
How Much Does a Nickel Weigh?
Since the United States Mint began producing nickels in 1866, the specifications remain fairly constant. The five-cent coin is composed of 75 percent copper and 25 percent nickel. It weighs 5 grams with a tolerance of ± 0.194 grams and has a diameter of 21.21 millimeters. Nickels produced between 1866 and 1883 had a slightly smaller diameter of 20.5 millimeters and therefore were slightly thicker than today's standard.
Since nickels produced in the United States are composed mainly of copper, Congress once again intervened to change the composition of the coin to save copper for the manufacture of munitions to fight the war in Europe. From 1942 until 1945, five-cent coins were composed of 56 percent copper, 35 percent silver, and 9 percent manganese. These coins are easily distinguishable by the large mint mark located above the dome of Monticello on the reverse.
How Much Does a Dime Weigh?
Since 1965, all United States dimes have outer layers of 75 percent copper and 25 percent nickel clad to a core of pure copper. A 10-cent coin weighs 2.268 grams with a tolerance of ± 0.091 grams and a diameter of 17.91 millimeters. Roosevelt dimes dated before 1964 were composed of 90 percent silver and 10 percent copper and weighed 2.5 grams with a tolerance of ± 0.097 grams.
How Much Does a Quarter Weigh?
All 25-cent coins manufactured since 1965 have outer layers of 75 percent copper and 25 percent nickel bonded to a core of pure copper. They weigh 5.67 grams with a tolerance of ± 0.227 grams and a diameter of 24.26 millimeters. Washington quarters manufactured in 1964 and earlier have a composition of 90 percent silver and 10 percent copper, weighing 6.25 grams with a tolerance of ± 0.194 grams.
How Much Does a Half-Dollar Weigh?
The United States half-dollars manufactured for circulation since 1971 have outer layers of 75 percent copper and 25 percent nickel adhered to a core of pure copper with a diameter of 30.61 millimeters. These coins weigh 11.34 grams with a tolerance of ± 0.454 grams.
Kennedy half-dollars minted from 1965 through 1970 have a composition of 40 percent silver and 60 percent copper and weigh 11.5 grams with a tolerance of ± 0.4 grams.
Franklin and Kennedy half-dollars minted between 1947 in 1964 are composed of 90 percent silver and 10 percent copper that weigh 12.5 grams with a tolerance of ± 0.259 grams.
How Much Does a Dollar Coin Weigh?
The United States began producing silver dollars in 1794. The composition, diameter, and weight have changed drastically over time. The United States Mint currently produces the Native American dollar series. These coins are minted with outer layers of 77 percent copper, 12 percent zinc, 7 percent magnesium, and 4 percent nickel clad onto a core of pure copper. These coins weigh 8.1 grams and have a diameter of 26.5 millimeters. These are the same specifications also used to manufacture the Presidential dollar coin from 2007 to 2016.
Other dollar series included the Susan B. Anthony dollar with outer layers of 75 percent copper and 25 percent nickel bonded to a core of pure copper. Anthony dollar coins weigh 8.1 grams with a tolerance of ± 0.3 grams and a diameter of 26.5 millimeters.
The last of the "big dollars" was the Eisenhower dollar that also had the copper-nickel clad composition, except they weighed 22.68 grams with a tolerance ± 0.907 grams and a diameter of 38.1 millimeters. Several silver Eisenhower dollars were specially made for coin collectors. These weighed 24.5 grams and were minted with outer layers consisting of 80 percent silver and 20 percent copper bonded to an inter-core of 20.9 percent silver and 70.91 percent copper. These special collector coins were produced in both business strike and Proof finish.
All silver dollars minted from 1794 until 1935 were composed of approximately 90 percent silver and 10 percent copper. They weighed anywhere between 26.956 grams and 26.73 grams. The diameter varied between 39.5 millimeters and 38.1 millimeters.