The SF mint actually did close at the end of 1955, and didn't reopen for production of proofs until 1968, so if the OP's piece was created before '68 it was reasonable to believe that the mint was actually gone.
So it was formally closed and opened again later, interesting. Makes this set somewhere around 45 years old at the minimum.
I like it for $25 all day long. BTW I still occasionally find the cent and nickels in roll searches. Wish they were still minting cents there with S mintmarks.
never seen this, I'm not a huge fan of the way these are toning in that packaging....kind just slowly turning black from the rim in.
Yeah, I pulled them out. The cent was pretty much gone, the nickel was circulated (?) in the first place, the dime is unattractive, and I'd say the Quarter and Half should have been pulled 5-10 years ago, but still don't look that bad. I'll give them a quick bath in acetone sometime over the next week and see what they look like after. I kept the holder, just because I think it's an interesting little piece of numismatic americana. I'd say the half and quarter are solid MS65's.