Coins of the United States dollar

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Top row: Sacagawea Dollar, Lincoln Cent, and Roosevelt Dime.
Bottom row: Kennedy Half Dollar and Westward Journey Series Jefferson Nickels

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2005 State Quarters: California, Minnesota, Oregon, Kansas, and West Virginia

United States coinage was first minted by the new republic in 1792. New coins have been produced every year since then and they make up a valuable aspect of the United States currency system. Today circulating coins exist in denominations: $0.01, $0.05, $0.10, $0.25, $0.50, and $1.00. Also minted are bullion and commemorative coins. All of these are produced by the United States Mint. The coins are then sold to Federal Reserve Banks which in turn are responsible for putting coins into circulation and withdrawing them as demanded by the country's economy.

Current coinage

Today four mints operate in the United States producing billions of coins each year. The main mint is the Philadelphia Mint which produces circulating coinage, mint sets and some commemorative coins. The Denver Mint also produces circulating coinage, mint sets and commemoratives. The San Francisco Mint produces regular and silver proof coinage. The West Point Mint produces bullion coinage (including proofs). Philadelphia and Denver produce the dies used at all of the mints. The proof and mint sets are manufactured each year and contain examples of all of the year's circulating coins. These and the other non-circulating coins can be purchased directly from the US Mint.

Circulating coins

Value	Obverse	Reverse	Common Reference
$0.01	Abraham Lincoln (since 1909)	wheat (1909–1958) Lincoln Memorial (1959–present)	Penny, Cent
$0.05	Thomas Jefferson (since 1938)	Monticello (1938–2003) Westward Journey Series (2004–2005) Monticello (since 2006)	Nickel
$0.10†	Franklin D. Roosevelt (since 1946)	Torch, oak branch, olive branch (since 1946)	Dime
$0.25†	George Washington (since 1932)	Bald eagle (1932–1998)‡ Bicentenial colonial military drummer (1976) State Quarter Series (1999–2008)	Quarter
$0.50†	John F. Kennedy (since 1964)*	Great Seal of the United States surrounded by 50 stars (since 1964)‡	Half dollar, 50-cent piece
$1.00	Dwight D. Eisenhower (1971–1978)	Bald Eagle on Moon (Apollo 11 Mission Insignia) ‡	Eisenhower dollar
	Susan B. Anthony (1979–1981; 1999)	Bald Eagle on Moon (Apollo 11 Mission Insignia)	SBA dollar
	Sacagawea (since 2000)*	Bald Eagle in flight	Gold(en) dollar
	Presidential (start 2007)**	Statue of Liberty	Gold(en) dollar

Note:
†: Dimes and quarters from before 1965 and half-dollars from before 1971 generally don't remain in circulation due to being removed for their silver content. The half-dollar retained a lower silver content between 1965 and 1970

‡: In 1975 and 1976 bicentennial coinage was minted. Coins were dated 1776-1976. The quarter featured a Colonial Drummer, the half dollar Independence Hall and the dollar coin featured the Liberty Bell superimposed on the Moon.

*: The Kennedy half-dollar (since 2003) and Sacagawea dollar (since 2002) are no longer being released for general circulation but are still minted for collectors and are available in uncirculated rolls, mint sets and proof sets from the United States Mint.

**:The Presidential Dollar series will feature portraits of all deceased U.S. Presidents in a rotating order based upon inauguration date.

Bullion coins

Non-circulating bullion coins have been produced each year since 1986. They can be found in silver, gold and also platinum since 1997. The face value of these coins is symbolic and does not actually reflect the value of the precious metal contained therein.

Type	Diameter	Fineness	Face Value	Content
American Silver Eagle	40.6 mm	999 fine silver	$1	one troy ounce (~31.1 grams)
American Gold Eagle	16.5 mm 22.0 mm 27.0 mm 32.7 mm	916 fine gold (22 karat)	$5 $10 $25 $50	1/10 troy ounce (~3.11 grams) ¼ troy ounce (~7.78 grams) ½ troy ounce (~15.6 grams) one troy ounce (~31.1 grams)
American Platinum Eagle	16.5 mm 22.0 mm 27.0 mm 32.7 mm	999.5 fine platinum	$10 $25 $50 $100	1/10 troy ounce (~3.11 grams) ¼ troy ounce (~7.78 grams) ½ troy ounce (~15.56 grams) one troy ounce (~31.1 grams)
American Buffalo	32.7 mm	999.9 fine gold (24 karat)	$50	one troy ounce (~31.1 grams)

Commemorative coins

Modern commemoratives have been minted since 1982. A complete list is available: Modern United States commemorative coins.

Composition of US Modern Commemorative Coins

Type	Total Weight	Diameter	Content	Weight of Precious Metal
Half Dollar	11.34 grams	31.75 mm (1.25")	92% Cu, 8% Ni	(none)
Dollar	26.73 grams	38.1 mm (1.50")	90% Ag, 10% Cu	24.057 grams Silver (~ 0.84 oz)
Half Eagle	8.359 grams	21.59 mm (0.850")	90% Au, 6% Ag, 4% Cu	7.523 grams Gold (~ 0.26 oz)
Eagle	16.718 grams	26.92 mm (1.06")	90% Au, 6% Ag, 4% Cu	15.05 grams Gold (~ 0.53 oz)
First Spouse Eagle Bullion	14.175 grams	26.49 mm (1.043")	99.99% Au	14.175 grams (1/2 oz)

Obsolete coins and denominations

• Half cent: $0.005, copper
• Large Cent: $0.01, copper
• Two-cent piece: $0.02, copper
• Three-cent piece: $0.03, silver and copper/nickel
• Half dime: $0.05, silver
• Twenty-cent piece: $0.20, silver
• Silver dollar: $1.00, silver (some modern commemoratives are minted in this denomination)
• Gold dollar: $1.00, gold
• Quarter-eagle: $2.50, gold
• Three-dollar piece: $3.00, gold
• Stella: $4.00, gold (not circulated)
• Half-eagle: $5.00, gold (some modern commemoratives are minted in this denomination)
• Eagle: $10.00, gold (some modern commemoratives are minted in this denomination)
• Double eagle: $20.00, gold
• Fifty-dollar coin or "Half Union" (Commemorative only, California territorial gold, pattern piece)

Note: It is a common misconception that "eagle"-based nomenclature for gold U.S. coinage was merely slang. This is not the case. The "eagle," "half-eagle" and "quarter-eagle" were specifically given these names in the Coinage Act of 1792. Likewise, the double eagle was specifically created as such by name ("An Act to authorize the Coinage of Gold Dollars and Double Eagles", title and section 1, March 3, 1849).

Some modern commemorative coins have been minted in the silver dollar, half-eagle and eagle denominations.

Criticisms

Unlike many world currencies the values of US coins are not inscribed in numerals on the coin. Instead the value is written in English words presenting potential difficulties for visitors to the country who do not speak the language well or English speakers unfamiliar with the currency. Furthermore the coins' inscriptions do not follow a pattern in describing the value: "One Cent" (penny), "Five Cents" (nickel), "One Dime" (worth 10 cents), "Quarter Dollar" (worth 25 cents), and "Half Dollar" (worth 50 cents).

For historical reasons the size of the coins does not increase with their face value. Both the one cent and the five cent are larger than the ten cent and the less common 50 cent coin is larger than the recent Sacagawea and Susan B. Anthony dollar coins. The sizes of the dime, quarter and half dollar are holdovers from before 1965 when they were made from 90% silver and 10% copper; their sizes thus depended upon the amount of silver needed to equal the face value. The diameter of the current dollar coins was introduced in 1979 with the Susan B. Anthony dollar not only as a concession to the vending machine industry which wanted a smaller dollar coin usable in their machines but also as an increase in the amount of seignorage for the US Government (the difference between what a piece of money costs to produce and its face value or the "profit margin").

External links

• United States Mint
• United States Virtual Coin Museum
• Page of 1792 Mint and Coinage Act (Describes the first completely regulated U.S. coinage system.)
• What have they done to our coins? - An article visually exploring recent changes to U.S. modern coin designs.
• Complete US Coin Histories By year and type.
• Metal detecting for collectible coins - How to find historic coins with a metal detector.