Recently, planes have been crossing the Atlantic Ocean with some pretty surprising cargo.

The flights take off from Europe bound for New York. They carry the usual passengers, vacationers, business people, and the usual luggage.

But along with all those identical black roller bags, they're carrying something else.

Many, many tons of gold are flying over the Atlantic in the cargo hold of passenger planes.

Gold bars?

Bars, yeah, bars, Bars, bars are gold.

That's my colleague Joe Wallace.

Would I ever know if gold was on my flight?

No, no, no.

They would never tell you.

Then you'd be a target, right, for some armed robbery.

That's true.

Are there load balancing issues involved?

Excellent question. The limitation, I think, is financial. You can generally take up to five tons of gold, which is about half a billion dollars of gold on a flight. And that's because the insurers won't insure anything above that.

Well, that's a lot.

It's a lot. Yeah, it's a lot of gold.

You may have heard about the gold market. Maybe you even follow it a little bit.

But the details of how this market actually works, the actual mechanics of it, can get pretty complicated.

It turns out the story of how gold ended up on planes involves vaults deep under the

streets of London, Swiss gold refiners, New York gold traders, and one U.S. president.

Welcome to The Journal, our show about money, business, and power.

I'm Jessica Mendoza.

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