So I've been looking into rare coin collecting lately and stumbled down this rabbit hole about minting errors that are actually worth serious money. Like, we're talking five figures for some of these things.

The one that really caught my attention is the 2000-P Sacagawea coin error. Apparently this collector named Tom DeLorey spotted it by accident when the coins first hit Walmart in early 2000. The reverse design on these sacagawea coin error pieces got changed at the last minute—something about the tail feathers on the eagle—and only 19 of them ended up in circulation. Each one goes for anywhere between $15k and $50k depending on condition. That's wild.

What's interesting is that the U.S. Mint initially denied there was even a difference, but the designer came out and confirmed he'd tweaked the design. So now collectors hunt for these 'mule' coins where the front and back dies don't match up. The sacagawea coin error became kind of famous in collector circles because of how rare it is.

But it's not just the Sacagawea situation. There's a whole market for minting mistakes. The 1955 DDO Lincoln Cent with the doubled die is iconic—people pay over a grand for those. Then there's the 1937-D Buffalo Nickel with three legs instead of four, which sounds absurd but apparently goes for $500-$2,500. The craziest one I found was the 1975 Roosevelt Dime without the S mintmark—one sold for nearly half a million.

The advice from collectors is basically: check your coins before you spend them. These rare pieces are apparently just sitting in bank rolls waiting for someone to actually look at what they're holding. Seems like an oddly fun way to potentially score something valuable.