what nickels have silver in them
Earlier nickels are not worth saving for their metal content any moreso than modern nickels because the alloy is the same today as it has been since 1866. EXCEPT for the War Nickels 1942-1945 with the large mintmark above Monticello (including a 'P' for Philly) which have silver in them and are worth well above face. You should look for earlier-date nickels with mintmarks and key dates (e.g., 1950-D) and the very early Jeffersons.