The first couple years they made the IH they weren't copper. I think they were an alloy close to a copper nickel mix and they were yellow. I know they put the shield on them in 1860.
The copper nickel ones were from 1859 to 1864. they were made of the same mix of metel as the flying eagle cents, which were made for only three years 56 to 58.
Just stuff to know if you cant find a date.
Old Dog