Some coins have minute flaws that raise their face value by hundreds or even thousands of dollars.
However, if you don't know what kinds of mistakes to look for, you might be walking around with valuable coins without even realizing it.
Coin collector Justin Couch took to TikTok to explain the minute error that caused the nickel to sell for $880 on eBay after spotting it.
On YouTube, TikTok, and Instagram, Justin has more than 600,000 followers. He frequently shares tips on buying rare coins and other collectibles.
Before being sold, the $880 coin drew more than 31 bids from collectors, but to the untrained eye, it might just look like any other nickel.
The tails, or reverse side, of a standard US nickel from 1913 to 1938 featured a buffalo.
All of the Buffalo Nickel's titular creatures were supposed to have four legs, but some 1937 nickels were made with only three.
1937 three-legged buffalo coins range in value from $608 to $1,655, according to USA Coin Book, depending on their condition.
The Professional Coin Grading Service reports that the highest auction bid for a circulated 1937 three-legged buffalo was $2,400.