Coins are a form of currency used in the United States. They are instrumental in overseeing the economy. Coins were introduced by the US Congress on April 2, 1792 under the Coinage Act (also known as Mint Act). The first coin went into circulation on March 1, 1793.
American coins are made of varied materials like copper, nickel, zinc, gold, silver. The modern American coin size is 18mm in diameter and 1.75mm thick.
Quarters are part of the US dollar system with a face value of 25 cents (1/4 dollar). Dimes are part of the US dollar system with a face value of 10 cents (1/10 dollar). Nickels have a face value of 5 cents (1/20 dollar) and pennies have a face value of 1 cent (.01 dollars).