The United States Mint says that a dime is 17.91 mm (0.705 inches) in diameter, 1.35 mm thick, and 2.268 grammes in weight (0.08 ounces). This coin is the thinnest and has the smallest diameter of any U.S. coin.
Cupronickel is an alloy made of copper, nickel, and other things. It is used to make dimes. Dimes have 8.33 percent nickel and the rest is made up of copper and sometimes a small amount of manganese. The copper-nickel in dimes makes them look silver.
There are 118 reeds along the edge of a dime. These are the grooved lines that go around the edge of dimes. They are there to stop people from making fake coins. People tried to get the gold and silver out of the edges of dimes, which were once made of gold and silver.