US five cent coins contain over 7 cents worth of raw material as of this afternoon, mostly copper and of course, nickel. If there is inflation, the prices of metal will increase, and the coin will have 8, 9, 10 cents worth of metal. Pre-1965 dimes contain over $2.42 of metal today, while pre-1965 quarters have over $6 worth of metal.
There is an old saying, “Don’t take any wooden nickels,” which seems ridiculous on the face of it, because why would a “nickel” be made of wood?
Perhaps that was the point.