I noticed that on my 1971 and 1972 nickels that I was going through, the mint mark is small compared to say. 1985. Why is this?
Up till the early 1990s the mintmarks were punched onto the dies by hand. The punch that they used might have changed from year to year.... Speedy
If I'm not mistaken, in the 70's, it was even the same punches that they used to punch by hand on everything from the Dime up to the Eisenhower, hence the mintmark was small enough to fit on the dime.