​West Texas Intermediate (WTI) Crude was right around $90 a barrel on Tuesday — lower than peaks earlier this month but still not cheap.

But that WTI price — which “Marketplace” and outlets around the world report all the time — is a financial measure. It represents the future price of a barrel of U.S. oil — on paper. It’s not what a refiner is actually paying for a shipment of crude oil today. It could actually cost them a lot more. ​

​​There are so many different crude oils and prices — WTI, Brent, OPEC, Mexican, Indian. There’s even a crude price called Mars.

“Mars is actually an offshore platform in the Gulf of Mexico,” said Tom Seng, a professor of energy finance at Texas Christian University.

But lately, something unusual has been happening with Europe’s benchmark crude oil, Brent, said Joe DeLaura, senior energy strategist with Rabobank.

“The current state of unreality between futures prices for oil and physical prices for oil is just blowing my mind.,” DeLaura said. “We now have a $26 spread again between Brent physical and Brent futures.”

That’s a big gap between the price being paid for Brent futures — the financial world’s price of oil — versus what people are actually paying to get a physical delivery of a barrel of oil.

“We just keep talking about futures,” DeLaura said. “Like, oh, futures are down $4 today. Okay, who cares? Well, futures don't mean anything. Physical oil means everything.”