Just when you thought $10 was only $10.

Now, whenever you get one, you'll need to look closer.

Believe it or not, that seemingly ordinary $10 bill could hold a value of over $100K. It's a fascinating world of currency we're about to delve into.

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Here's what you need to look for. Like stamps and other printed materials, you first want to look for misprints, errors, and serial numbers with something extra or different. For instance, a unique serial number, a star symbol at the end of the serial number, or a different seal color could indicate a rare $ 10 bill.

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For example, some $10 bills have a star (*), which could mean big things. When found at the end of a bill's serial number, this star symbol indicates that the bill is a "star note."

These types of bills are called "star notes," and according to Collectibles and Currency:

These star notes, with their unique symbol at the end of the serial number, are not your everyday bills. They're printed in much smaller quantities than regular notes, making them a rare and exciting find for collectors.

That means those $10 bills are rare and replacements, meaning collectors spend more than face value to add them to their collections.

But star notes are not the only ones that hold value. Gold Seal Gold Certificate Notes, Brown Seal National Bank Notes, Yellow Seal North Africa Notes, and Blue Seal Silver Notes are all selling for much more than their face value. There's a world of potential profit waiting to be explored.

Check out OldMoneyPrices.com to see if you have $10 in your wallet that is worth more than its face value.

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