You probably have a jar of dimes sitting on your dresser. Most of them are worth exactly ten cents. But there’s a specific kind of "oops" from the San Francisco Mint that turned a couple of copper-nickel discs into six-figure lottery tickets. We're talking about the 1975 No S proof Roosevelt dime. It is, quite literally, one of the rarest pieces of United States coinage ever to escape a mint building. Only two are known to exist. Just two. That’s it.
Think about that for a second.
In the world of numismatics, rarity is usually measured in the thousands or hundreds. When you get down to single digits, the "market price" basically becomes "whatever a billionaire is willing to pay at auction." For decades, this coin was the Loch Ness Monster of the coin world—people heard rumors, but nobody could prove it was real until the first one surfaced in the late 1970s.
What Actually Happened at the San Francisco Mint?
To understand why the 1975 No S proof Roosevelt dime matters, you have to understand how proof coins are made. Unlike the dimes you get in your change at Starbucks, proof coins are struck specifically for collectors. They have these mirror-like backgrounds and frosted foregrounds. Starting in 1968, all proof coins were supposed to be struck at the San Francisco Mint and carry a little "S" mint mark right above the date.
Someone messed up.
A pair of dies—the heavy metal stamps that press the design onto the coin—was sent from Philadelphia to San Francisco without the "S" mint mark. Usually, quality control catches this. They’re supposed to look at the dies, realize the mark is missing, and grind them down. For some reason, at least one die set started banging out dimes. Most experts, like those at PCGS and NGC, believe a small batch was struck before the mistake was noticed. Then, those coins were packaged into the standard 1975 Proof Sets and mailed out to unsuspecting collectors.
Imagine opening a $7.00 proof set you bought from the government and realizing you're holding something worth as much as a suburban home. It’s the ultimate "Right Place, Right Time" scenario.
The Mystery of the Two Known Dimes
For a long time, the hobby only knew about one. That first coin was discovered by a collector in California shortly after the 1975 sets were released. He sent it to Coin World, and the news sent the collecting community into a literal frenzy. Everyone started ripping open their 1975 proof sets. People were using magnifying glasses until their eyes hurt.
📖 Related: Kiko Japanese Restaurant Plantation: Why This Local Spot Still Wins the Sushi Game
They found nothing.
Well, almost nothing. A second one eventually appeared, and for nearly 50 years, those have remained the only two verified examples. Fred Weinberg, a legendary error coin expert, has handled these coins and confirmed their authenticity. It’s not just a "missing letter." It’s a systemic failure of the mint’s verification process that resulted in a unicorn.
One of these coins stayed in the same family for decades. A lady in Ohio and her mother bought two proof sets in 1975. They noticed the missing "S" on one of the dimes and just... kept it in a bank vault. They didn't brag. They didn't go to the papers. They just sat on it. When that coin finally hit the auction block via GreatCollections in late 2024, it was a massive deal. It wasn't just a coin sale; it was the closing of a chapter in a 50-year-old mystery.
Why You Can’t Just Find the 1975 No S Proof Roosevelt Dime in Your Pocket
I need to be super clear about this because it trips people up all the time. You will not find the 1975 No S proof Roosevelt dime in your pocket change.
Why? Because the Philadelphia Mint also made dimes in 1975, and those don't have mint marks either.
Here is the secret: The "No S" error is only valuable if it is a proof coin. You have to look at the finish. If the coin has a dull, satin look and looks like every other dime, it’s a Philadelphia business strike. It's worth ten cents. If the coin looks like a mirror—if you can see your reflection in the background and the design looks like it’s made of white sugar—then you might be looking at a proof.
If you have a proof dime from 1975 and it doesn't have an "S," you've found the third one. And if you find the third one, you’re looking at a payday that could easily clear $500,000.
👉 See also: Green Emerald Day Massage: Why Your Body Actually Needs This Specific Therapy
The Market Value: Numbers That Make Your Head Spin
Pricing a coin like the 1975 No S proof Roosevelt dime is tricky because they sell so infrequently. You can't just look up a "blue book" value because there isn't a steady supply.
When the "Ohio" specimen was put up for auction, the bidding blew past $300,000 almost immediately. Previously, the other known example sold for $456,000 back in 2019. Honestly, in today’s market, where high-end assets are being snatched up by diversified investors, it wouldn’t be shocking to see one of these cross the half-million-dollar mark.
Compare that to other "No S" errors.
- The 1968 No S Roosevelt Dime: Rare, but dozens exist. Worth maybe $20,000 to $40,000.
- The 1983 No S Roosevelt Dime: A few thousand exist. Worth about $500.
- The 1990 No S Lincoln Penny: Found in many sets. Worth about $3,000.
The 1975 dime is the king of them all. It’s the rarest of the "No S" proof errors by a huge margin. It's the "1913 Liberty Head V Nickel" of the modern era.
Real Advice for the Amateur Hunter
So, you want to find one? It’s not impossible, but you have to be smart about how you search. You aren't looking in Coinstar machines. You’re looking in dusty coin shops and estate sales.
Look for the "1975 United States Proof Set." It’s a purple plastic case. Inside, you’ll see a penny, a nickel, a dime, a quarter, a half dollar, and a dollar coin. Most of these sets sell for about $10. Most dealers don't even look at the dimes anymore because they've checked a thousand of them and found nothing.
But dealers are human. They get tired. They get lazy.
✨ Don't miss: The Recipe Marble Pound Cake Secrets Professional Bakers Don't Usually Share
If you're at a show, or browsing a local shop, and they have a stack of 1975 proof sets, check the dime. Every. Single. Time. Look specifically at the space above the date. If it's blank, don't scream. Don't make a scene. Just buy the set for the $10 or $15 they're asking, walk out the door, and call a major grading service like PCGS.
Is There a Third One Out There?
Statistically? Probably.
Mints don't usually strike just two of anything. Coins are minted in "runs." When a die is put into a press, it usually stays there for a while. It’s highly likely that a full sheet or a full hopper of these dimes was struck. Most were probably caught and destroyed, but if two made it into sets, it’s a safe bet that a few more are sitting in basements in some forgotten collection.
Some people think there might be as many as 20 or 30 of them. If that’s true, they are the most well-hidden coins in American history. People have been hunting for the 1975 No S proof Roosevelt dime for half a century, and we're still stuck at two.
Actionable Steps for Your Search
If you're serious about this, don't just wander around aimlessly. Use a strategy.
- Buy Unopened Sets: Look for 1975 Proof Sets that still have the original cardboard Treasury mailing envelope. While someone could have opened it and resealed it, these are your best "unsearched" lottery tickets.
- Verify the Finish: Learn the difference between a "Proof" and a "Business Strike." A proof will have "cameo" contrast—a sharp, frosted portrait against a shiny background.
- Use a Loupe: Don't trust your naked eye. A 10x jeweler's loupe will show you if an "S" was polished off (a common scam) or if it was truly never there.
- Check Estate Auctions: Old-timers who bought sets in 1975 and just threw them in a drawer are your best source. They haven't checked for errors. Their grandkids won't check either.
You’re looking for a needle in a haystack, but the needle is made of gold. Even though the 1975 No S proof Roosevelt dime is a legend, it’s a legend built on a very real mistake. It’s the kind of thing that keeps the hobby alive. It’s the dream that you can turn a pocket-change denomination into a life-changing windfall just by paying attention to the details.
Stay focused on the 1975 sets. Ignore the 1975-D (Denver) and the 1975 Philadelphia strikes you find in your car's cup holder. They won't make you rich. But that one purple plastic box from San Francisco? That might just be the one. Get yourself a loupe and start hunting. The third one is out there somewhere.