I decided to go through the jar of coins on our dresser and found these 2 1964 nickels. If I'm not mistaken, this is the last year of 90% silver coins?
Kingskid is correct. The only Jefferson nickels that were silver alloy were from late 1942 - 1945. They can be easily identified by the large mint mark on the reverse, above Monticello.
Please get a good guide on United States coins. It can be very helpful. I pick one up every few years
World War II prompted the rationing of many commodities. Nickel was highly valued for use in armor plating, and Congress ordered the removal of this metal from the five-cent piece, effective October 8, 1942. From that date, and lasting through the end of 1945, five-cent pieces bore the regular design but were minted from an alloy of copper, silver and manganese - Silver content of 35%. So, 1942 - 1945 are partial silver. 1964 - Worth a whopping 5 cents