It’s an oft-repeated trope that having a hobby can have a positive impact on a person’s well-being—and research has found connections between hobbies and better work performance, improved health, and lower stress, among other benefits.

But if you’re a coin and banknote collector, that hobby can be beneficial to your pocketbook as well.

This spring, New York’s Stack’s Bowers Galleries will auction off a U.S. Silver Certificate from 1891 Although the so-called “Marcy Note” has a face value of $1,000, the bill is expected to fetch a sales price between $2 and $3 million dollars, as reported by Bloomberg.

“I’d bet a lot of money that another one of these notes won’t turn up,” Peter Treglia, the director of currency for Stack’s Bowers, told Bloomberg.

The bill is named for Senator William Marcy, whose face appears on the front.

Marcy was New York Governor from 1833-1838, and served as a U.S. Senator and later Secretary of War under James K. Polk.

Although the U.S. Treasury printed about 1,500 Marcy Notes, the bills never entered public circulation, and only two are known to have survived. One is in the Smithsonian; the one being sold currently belongs to the currency collector Joel R. Anderson.

The “Grand Watermelon” banknote.
The “Grand Watermelon” Note. 

In the last few years, several auctions of unique U.S. tender have reached similarly high price points. Just last October Stack’s Bowers sold a rare $1,000 Treasury Note from 1890 for more than $2 million.

Named the “Grand Watermelon,” after the three large oblong zeros on the back, the bill is one of only seven in the world. No wonder it was dubbed the “Holy Grail” of American currency.

Like fine art or wine, notes and coins this unique are in limited supply—and contrary to popular belief, it’s exceedingly rare for missing bills to be found. “I’d bet a lot of money that another one of these notes won’t turn up,” Peter Treglia, the director of currency for Stack’s Bowers, told  Bloomberg. “Things are discovered all the time, but not of this magnitude.”

So before you try to break into the high-end coin collecting world, just remember that most of the money that’s out there is still worth the price written on the bill.

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