1955 Flat Pack Proof Set US Coins

1955 flat pack proof set of US coins w/original mail envelope from 1955 - open envelope but sealed coins and mint tag -- i am not a coin expert but i tried to take close ups of the coins so that you can see them and condition- * the nickel and quarter rims seem to have some type of residue appearing as dots and the penny has a dot up left near the head (I enlarged photos because it was hard for me to see ) --- would guess from the mint processing of package because it was not open..... being sold as pictured so please review all photos prior to purchase..