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In an increasingly cashless society, all physical currency has become comparatively rare: It’s never been easier for most people to simply use their credit card, Venmo, or saved payment information to complete most of their purchases. Even so, approximately $1.87 trillion in physical U.S. currency is still in circulation — the vast majority of which naturally consists of the six most common notes ($1, $5, $10, $20, $50, and $100). They weren’t always the most common, however, as America has produced many now-rare forms of currency throughout its financial history. Here are six of them.

Half-Cent Coin

Half cent coin, shown front and back, from 1835
Credit: Mark Kostich/ iStock

The next time you’re charged a fraction of a penny for something and bemoan the fact that you don’t have exact change, feel free to curse fate — and the U.S. Mint — for discontinuing the half-cent coin way back in 1857. Making the humble penny look like big money in comparison, it was introduced as a result of the Coinage Act of 1792 and had five different designs during its run. All of them were variations of Liberty herself, and the coin was made of 100% copper. A tenth of a cent is referred to as a mill (₥), a now-abstract unit of currency that lives on in accounting (and occasionally gas prices); milles were usually used for small purchases such as sales tax before losing most of their real-world value.

Two-Dollar Bill

A roll of several two-dollar bills
Credit: ozgurdonmaz/ iStock

No childhood was complete without a random $2 bill stored away for a rainy day, especially if it was gifted to you by a relative. Every kiddo’s favorite banknote featured Thomas Jefferson on the front (or obverse, as it’s called) and John Trumbull's painting "Declaration of Independence" on the back (reverse). The U.S. Currency Education Program estimates that there are still 1.2 billion in circulation today.

A lesser-known fact is that the note is actually still issued by the Federal Reserve Board, which orders new currency from the Treasury’s Bureau of Engraving and Printing (BEP) every year. Unlike the bills you're more familiar with, however, the $2 bill is only ordered every two to four years. There's a good reason for that: Most of these orders are to replace notes that have received too much wear and tear to remain in everyday use; because $2s aren't used as often, they don't need to be replaced as often. In some ways, this is actually a self-fulfilling prophecy: because people think the bills are uncommon, they treat them that way, inadvertently ensuring that they maintain this rarefied status.

Five-Hundred Dollar Bill

A five-hundred dollar bill on top of hundred dollar bills
Credit: m.czosnek/ iStock

Though it hasn’t been in circulation since 1969, the $500 bill is unique among discontinued currencies in that it's still considered legal tender. First introduced on a federal level in 1862, the high-denomination bill featured everyone from John Quincy Adams and William Tecumseh Sherman to Abraham Lincoln and William McKinley throughout its tenure. Now a sought-after collector’s item, it’s worth much more than $500 if you can get your hands on one.

Three-Cent Coin

A collector's three-cent coin
Credit: jlgeranis/ Shutterstock

The problem with three-cent stamps is that there's no way to buy them without receiving change back. Prepare to be amazed, dear reader, as such a coin used to exist from 1851-1889: the noble three-cent piece, whose convenience was unmatched in antebellum America. They were made of silver, which helped lead to their downfall: that precious metal was frequently hoarded during the Civil War, meaning that the three-cent coin wasn't as widely circulated as it was intended to be. Then, when the price of stamps was eventually increased, our intrepid hero’s utility was drastically reduced and it stopped being produced.

Five-Thousand Dollar Bill

A $5000 bill on a light green background
Credit: Public Domain/ Edit by Travel Trivia

There’s rare, and then there’s the $5,000 bill. Originally created to help fund the Revolutionary War, this fine specimen didn’t come into official government use until 1868, when another history-altering war was raging. It was blessed with a portrait of our fourth president (or James Madison, as his friends called him) and recalled by the 37th, one Richard Nixon, in an effort to prevent money launderers from carrying out their ill deeds with its assistance. Only a few hundred remain, making them as valuable as they are rare.

One-Hundred-Thousand Dollar Bill

Exterior of the Federal Reserve building
Credit: pabradyphoto/ iStock

Everyone knows that the $100 bill is the highest denomination of U.S. currency. What the $100,000 bill presupposes is ... maybe it isn’t? The note, which featured an image of Woodrow Wilson on the obverse, was never issued for public use or circulated into the general economy. Rather, the gold certificate was created at the height of the Great Depression (1934, to be precise) by the BEP for Federal Reserve Banks to make transactions with one another. Only 42,000 were made, and they can't be held by collectors due to legal reasons, but institutions like the Smithsonian and the Museum of American Finance are allowed to exhibit them.