Denver Unc Mint Set With No Mint Mark D Nickel All Other Coin's Have The D

1. A no "D" coin in a "D" set would be considered a packaging error. It happens.

2. I have no idea what you are calling an "error" in regards to the main door on Monticello.

3. Can mint sets be tampered with? Sure.

that is not damaged it's a raised.. on all of them. so 1971 no S is just packaging error as well? wait what about the penny one with no S mint mark packaging error too?

The 71 No "S" Proof was not a packaging error. The mint mark was not added to the die as it should have been. There were several other instances of this happening with proof sets in 1970 with the dime, in 1971 with the nickel and in 1990 with the cent. (There may be others, too).

Your "D" mint set with a no mint mark nickel is A Philadelphia minted coin that was asssembled in to the wrong set. It is a packinging error.

Your coins look normal to me. I do not think what you are seeing with the door is an error of any kind.

I believe the sets were most likely packaged at a contracted facility by contract employees. The bulk coins from each mint facility were shipped to a central facility where the packaging took place. When you've got coins coming and going and employees that probably are pretty much clueless things happen. The coins look the same to them.

That's how packaging errors happen.

Not adding an "S" mintmark on Proof dies is a whole other story. It happened multiple times over a 20 year period. The mint finally got tired of it and solved the problem by adding the mintmark to the master die instead of adding the mintmark by hand to each individual die.

Possible, but unlikely.

Denver Mint makes their own coins and do their own packaging. Denver Mint don''t make Philadelphia coins and don't do Philadelphia coin packaging etc. This is a mint error not a packaging error. The only difference is. it happens in uncirculated mint set; not in proof set. This is a rare find. Don't remove it from the plastic. That is your only proof.

I don't know if its uncommon or not but I was just looking at a Denver set that had a Philly nickel in it. All other coins were Ds.

The mint error can only occur in the "Proof set." This is brainwashing, opinion, not fact. I would be jealous, too, if I didn't have that coin.