well i was going threw some change when i came across four SILVER dimes the dates are 1964, 1963, 1962, and 1957. and to make sure they weren't counterfeit i hit them with a pencil. all of the passed except for the 1963. so i weighed it. (well really i compared its weight to the other silver coins) and it turns out it was lighter than the others! meaning it was copper/nickel. how much is this coin worth?