The United States dollar (USD/US$) is also referred to as the American dollar or the U.S. dollar. It is the official currency of the United States of America and its overseas territories. Coins available from the United States mint are made from a variety of metals.
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One American dollar is divided into 100 smaller units called cents. Here is a brief look into the history of currency in the U.S.:
- In 1781, Congress chartered the Bank of North America in Philadelphia as the first national bank. It was to support the financial operations of the fledgling government.
- In 1785, Congress adopted the dollar as the monetary unit of the United States.
- In 1792, the Coinage Act of 1792 created the U.S. Mint and established a federal monetary system with set denominations for coins, and specified the value of each coin in gold, silver, or copper.
- In 1861, the federal government circulated the first paper money.
What are Coins Made Of?
The metals used in coin production are specifically chosen to last a long time. The metal used must have excellent wear resistance and anti-corrosion properties, hence coins are usually made using base metal alloys.
Care should be taken to ensure that the value of the metal within a coin is not greater than the face value. This would allow smelters to melt the coins and re-sell them. To counter this problem, coins are now made from a combination of metals such as cupro-nickel. Cupro-nickel is silver in color with hard-wearing and excellent striking properties.
Precious metals such as silver and gold were previously used by the United States mint to make coins. However, due to the increasing price of these metals, they are only used now for making bullion coins or collectors’ coins. Other metals such as copper, nickel, and zinc are used to make ordinary coins.
Initially, pennies were made from copper, but during wartime years the penny was made from steel mixed with zinc so as to conserve copper for weapons and shell casings. Today, all pennies are made primarily from copper-plated zinc.
Coins that have a silver color include quarter, nickel, and dime coins, made using a copper-nickel combination.
In the past, only the faces of the coins were plated, which caused coins to rust. However, advanced technology has eliminated such problems. Today, steel is added to the making of all coins.
Metal prices have strong control over which metal is used, even if there are new technologies available.
Another day, another dollar...but how are they made? Credit: © 2013 Photos.com, a division of Getty Images. All rights reserved.
Materials Used in US Banknotes
The Bureau of Engraving and Printing (BEP) develops and produces United States currency notes. American banknotes or currency paper is made of 75% cotton and 25% linen. This is what gives the United States currency its distinct look and feel. The paper and ink used in the production of U.S. paper currency are as distinct as their design. The quality of the paper is very high, and it would take almost 4,000 double folds (first forwards and then backward) before a note will tear.
The BEP receives the paper in brown paper-wrapped loads of 20,000 sheets. Each sheet is tracked by the BEP as it passes through the production process. The total inventory of 20,000 sheets is constantly monitored to ensure that every sheet is accounted for. Currency paper is specifically made for the BEP by Crane Paper Company. For denominations of $5 and above, a security thread and watermark are already built into the US banknote material when it is received.
The approximate weight of a note, regardless of denomination, is 1g. In 1929, small-sized notes were introduced in the green color, as a pigment of that color was readily available in large quantities. The color was also known to have high resistance to chemical and physical changes. Psychologically speaking, green was identified with the strong and stable credit of the Government.
The currency design is updated with added complexity from time to time to make counterfeiting more difficult. It has also been updated with features that will aid the public in easily distinguishing the denomination. These features were designed keeping in mind the needs of people with visual impairments.
Specifications for Legal Tender Coins in the USA
The following table provides the specifications regarding legal tender coins in the USA.
| Denomination |
Metal used |
Composition (%) |
Weight (g) |
Diameter |
Thickness (mm) |
Edge |
No. of Reeds |
| Cent |
Copper -plated Zinc |
2.5 Cu Balance Zn |
2.500 |
0.750 in. (19.05 mm) |
1.55 |
Plain |
N/A |
| Nickel |
Cupro-Nickel |
25 Ni Balance Cu |
5.000 |
0.835 in. (21.21 mm) |
1.95 |
Plain |
N/A |
| Dime |
Cupro-Nickel |
8.33 Ni Balance Cu |
2.268 |
0.705 in. (17.91 mm) |
1.35 |
Reeded |
118 |
| Quarter Dollar |
Cupro-Nickel |
8.33 Ni Balance Cu |
5.670 |
0.955 in. (24.26 mm) |
1.75 |
Reeded |
119 |
| Half Dollar |
Cupro-Nickel |
8.33 Ni Balance Cu |
11.340 |
1.205 in. (30.61 mm) |
2.15 |
Reeded |
150 |
| Presidential $1 |
Manganese-Brass |
88.5 Cu 6 Zn 3.5 Mn 2Ni |
8.1 |
1.043 in. (26.49 mm) |
2.00 |
Edge- Lettering |
N/A |
| Native American $1 Coin |
Manganese-Brass |
88.5% Cu 6 Zn 3.5 Mn 2 Ni |
8.1 |
1.043 in. (26.49 mm) |
2.00 |
Edge-Lettering |
N/A |
How are Metal Coins Produced in the USA?
All U.S. coinage is minted by the United States Mint. The production of millions of metal coins per day is a complex process that requires men and machines to work together efficiently and in unison.
The six main steps in the manufacture of American coins are given below:
- The first step is known as blanking. Blanks are punched from coiled strips of metal measuring 13 in by 1,500 ft in a blanking press. The leftover webbing is cut up and recycled. The cent is the only coin that is stamped onto pre-made blanks.
- The next step involves annealing, washing, and drying of the blanks. The blanks are heated in an annealing furnace to soften them, and then they are sent through a washer and dryer.
- The third step is called upsetting, where the good blanks are passed through an upsetting mill so as to raise a rim around their edges.
- The fourth step is striking. The blanks are passed to a coining press. In the press, they are stamped with the designs and inscriptions which provide them with the authentic appearance of United States coins.
- The fifth step is inspection during which press operators use magnifying glasses to spot-check each batch of newly struck coins.
- In the sixth and final step, the coins have to be counted and bagged. This is done using an automatic counting machine which counts the coins and drops them into large bags. Forklifts transport the pallets of sealed bags to vaults for storage. From there trucks, take the new coins to Federal Reserve Banks, and later to local banks.
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