The remains of a 145-million-year-old dinosaur went under the hammer in France on November 16. Valued at millions of euros, its sale could set a new milestone in the booming market for fossils.

Dubbed “Vulcan,” the giant specimen is “the largest dinosaur skeleton ever to come to auction,” according to auction houses Collin du Bocage and Barbarossa.

The remains are believed to be those of an apatosaurus, extremely large herbivores that populated North America around 150 million years ago, in what scientists call the late Jurassic period. But the sale catalog says the exact species is still unclear and that an “official scientific identification will have to take place.”

The dinosaur stretches 67 feet (20.5 meters) from tip to toe—so long that part of its tail has been detached so it fits into the room where it’s on display in a castle outside Paris, ahead of the auction.

“Vulcan” was discovered in 2018 in Wyoming. Unearthing all the remains took three years. They were then sent to Europe for restoration.

As well as the skeleton, the buyer will also get an excavation map and GPS location for where it was found.

The dinosaur was originally estimated to be worth between $4 million and $6 million. But the record sale of a stegosaurus—dubbed “Apex”—in July has since helped push up its value.

Auctioneer Florent Barbarossa expected “Vulcan” to fetch at least $11 million—and maybe double that—at the November 16 auction.

But the increasingly lucrative market frustrates some academic paleontologists who feel the specimens belong in museums or research centers that can’t afford huge auction prices.

Collin du Bocage says the future buyer will grant scientists access to the dinosaur. “The buyer will commit to allowing public access to this dinosaur in the future. That’s why there’s no controversy. Private funds have financed its research and restoration.”

Visitor Cyril Fernandes shares his concerns about privatization: “It must be visible to as wide a public as possible. Privatizing like that, for just one person, depends on what's being done afterward, but I’m putting it into perspective. I’m thinking, well, if it’s just for purely personal pleasure...”

This article was provided by The Associated Press.