There should be a “D”, “P” or “S” above Monticello.

They’re also very dark colored nickels usually. The dirtiest looking nickel is likely your silver nickel.

Dimes, quarters and half dollars minted 1964 and earlier are 90% silver. They’re not as easily found these days but you can find them, for sure!

Kennedy half dollars 1965-1970 are 40% silver.

Who buys coins that contain silver? Jewelers, coin shops, pawn shops and reputable online retailers.
People also buy them on social media platforms and they can also be sold at your local auction houses. They’re super easy to liquidate as long as you know where.