I think this is a case of overpolished die, but would like other opinions. On the reverse, the two windows closest to the dome are empty. I included a photo of the reverse of another nickel with widows complete.
Interesting. I don't believe over polished dies are classified as a mint error but I believe it is worth a bit of money if you find the right collector. You would usually see over polishing on proof dies because the dies are fixed and wiped down so much. Back then mint employees would wait for the die to wear down and then replace it with a new one, (they were a bit lazy). I do have a buddy who wrote an article on his website about die mint errors if you want to check it out; it might help there's loads of cool stuff on there: http://www.error-ref.com/part_iv__die_errors/ But with most coins: it's probably cleaned or something. Overall, cool find.
My mistake on this one. I happened to think perhaps the reverse was made that way that year. I googled it and that reverse is what was shown. My comparison is a 1996. Quite a bit newer.
