https://apnews.com/article/rare-dime-auction-san-francisco-mint-574e1a50e1f80b310941ef373d3ca22d So.... only in proof sets. How many (sets) will show up on E-Bay or auctions labeled "unopened" or pictures of the outer cardboard sleeve with no 'coin' shots. Can't imagine anyone could "accidentally" take such a blurry shot that you can't tell if there's a mint mark or not and post it for sale.
Same article discussed here. https://www.cointalk.com/threads/coin-news.414032/ This and the other no-S proofs is why we have all the "no mint mark" garbage polluting people's minds.
So this is caused by a grease filled die right? Why is it considered a variety and not just an error?
No, it was caused by the omission of the mint mark when preparing the dies for SF proof coins. Apparently they can tell that it's not just a grease-filled die. ""No-S" Proof coins were the product of the way in which Proof dies were handled. Beginning in 1968, when the San Francisco Mint began striking Proof coins, all dies for Proof coins were prepared at the Philadelphia Mint. This was done by adding a mintmark to a normal P-Mint die. However, some dies escaped this process, thus we see "No-S" dimes in 1968, 1970, 1975, and 1983, "No-S" Nickels in 1971, and "No-S" Lincoln Cents in 1990. Any estimates of the number of "No-S" coins is strictly a guess, but all except for the 1975 No-S Dime have certified populations of between 24 and 242."
Thanks. So I'm assuming they used that die more than twice, so I assume there's either more out there, or the mint destroyed the rest.
That's the theory. From the same PCGS blurb: "The extreme rarity of the 1975 "No-S" Proof Dime can be explained in two ways (both plausible conjectures): 1. The error was discovered at the Mint in time to stop the press, but not before a very small quantity of sets had already gone out the door. 2. The coins were deliberately made. This explanation is not as far-fetched as it may seem, because other remarkable Proof errors emerged from the San Francisco Mint during the early 1970's (for example, a Proof 1970-S Washington Quarter struck over a 1900 Barber Quarter -- from Philadelphia)!" Seems like in 1975 they caught it sooner than the other years, so there are fewer examples. Why it happened multiple times over the course of many years, who knows. I don't buy theory #2 - mint sport - because it would have to be coordinated between someone in Philadelphia who deliberately didn't punch the mint mark and then someone in SF who coined them. I suppose someone in Philly might have deliberately done it for giggles and SF didn't notice it, but it seems more likely that it was just sloppy QC at both mints.
Some more info from Great Collections about the other "No S" coins: https://www.greatcollections.com/kb/catalog/1/No-S-Proofs--Why-Do-They-Exist-and-What-Are-They-Worth
The local news reported on this today, ending with the anchor saying "you know what that makes me want to do? Look at every dime in sight." So get ready for the influx of threads.
Problem with this statement Is that it's not the stamping of the dimes, rather the assembly of the sets from six different coins, that might have been manufactured on different days.
Poor coin dealers. Probably a good idea to keep a tray of 75 philly coins and a proof set out to convince the incoming hoard that they do not win the lottery
