Asked in US Coins
How many ridges are on a US dime?
What is a US dime made of?
The outer layers of a US dime are made of an alloy (a mixture of metals) of 75% copper and 25% nickel. The core is made of pure copper, for an overall content of 91.67% copper and 8.33%. Before 1965, the dime was made out of 90% silver and 10% copper. The dime has a edge with 118 ridges. This coin is 17.91 mm in diameter and is 1.35 mm thick - it is the smallest, thinnest and lightest US coin. There's more information at the Related Link