When Americans travel, our money goes with — and not just in a metaphorical sense. Where people go, coins get left behind. Meanwhile, the pennies we drop at home get swept into trash heaps and scrap yards, falling out of sight and out of mind. But that doesn’t mean they don’t exist — and even if they’re beat up, it doesn’t mean they lose their value.

The Wall Street Journal reports this week on the weird and lucrative market of coin repatriation. Money that has traveled around the world can come back home, and those pennies add up.

How many nickels, dimes, and quarters have you lost in your car over the years? Now multiply that by 315 million Americans and the more than 250 million cars we collectively own, and it adds up.

When those cars are scrapped and shredded, the metal goes overseas, often to China. And that’s where the repatriation business comes in.

A bunch of hired hands go through all that salvage and pulls out the coins. The man behind the repatriation business then collects them in bulk, from various salvage yards, and ships them to a partner in the U.S. The American partner then turns in all those coins to the Mint, which will buys back for nearly face value.

It adds up — big. The U.S. Mint has paid out more than $100 million in coin redemption since 2009, the WSJ reports. And it’s not just American money, either: repatriation takes place for British coins too, for example.

If it sounds like maybe that fat wad of cash is too good to be true, well, the feds think so too. So many more coins started pouring in since 2009 that law-enforcement officials are thinking a bunch of them have to be fake.

The coin reimbursement program shut down last year, and officials detained $664,000 worth of coins from our cunning entrepreneur. While the man profiled in the WSJ piece was not accused of any wrongdoing, federal prosecutors allege three others in the same line of work have been importing counterfeit coins.

Lost in the Seat Cushions, There’s $100 Million in Spare Change

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