One of the largest and most complete *Tyrannosaurus rex *skeletons ever discovered is set to go on the auction block in Las Vegas in October.

The 66 million-year-old fossil was found 22 years ago in South Dakota and has come to be known as Samson. It is 40 feet long and 15 feet tall and consists of around 170 bones, more than half of a complete skeleton.

"In the last 110 years, there's been a total of 46 specimens found of Tyrannosaurus rex of which this is the third most complete and has the finest skull," said Tom Lindgren, who is co-director of natural history for the auction house Bonhams & Butterfields.

The last time a T. rex was auctioned, the most complete specimen ever found, known as Sue, went for more than $8 million dollars. The winner was the Chicago Field Museum.

Sue was still in pieces and unprepared when she was put on the block, and was only expected to fetch around $1 or 2 million. Lindgren hopes Samson will exceed his estimated worth. One thing he has going for him is that he is fully prepared and mounted and ready to go on display.

"I'm going to estimate it's in the neighborhood of $2 to 8 million, but it could easily go for upwards of $10 million," Lindgren said. "I want to hold the record for a natural history auction."

Samson is clearly the star of the upcoming auction, which will be held October 3 at the Venetian casino, but there will be more than 50 other lots of rare specimens.

Highlights include a 25-foot-long shark, the largest fossil shark ever found.

Lindgren has also secured a reconstructed shark jaw with a full set of real teeth that stands eight feet tall and 10 feet wide and belonged to a shark that was probably around 80 feet long.

He's trying to finalize the largest bony fish skeleton ever found, which is 17 feet long. Just 10 minutes before speaking with Wired.com, Lindgren learned he also has a woolly mammoth that stands around 12 feet tall.

"The items we have in this auction are definitely museum standard, or better," he said. "Most of the museums in the world don't have anything near what we have in this auction."

The auction items will be on display to the public during Labor Day weekend, as well as for the two weeks preceding the auction.

Samson's skull was discovered intact, unlike most skulls, including Sue's, which are in pieces. There are bite marks from other dinosaurs and places where the bone has been eaten away by infection.

"This animal, when it died, was in a lot of pain," Lindgren said. "But we don't know what killed it."

After Samson was originally excavated from a ranch by fossil collectors, it was sold to a private buyer from the Isle of Man, who then sold it to its current American owners.

Lindgren is hoping Samson lands somewhere the public will be able to appreciate him for years to come and is pushing for museums to participate.

At least 20 institutions have shown interest, "but then there's always the elite that have a lot of money and like unique and unusual items, especially the Hollywood types," he said. "There are a couple of major actors that are collectors of dinosauria."

Because T. rex is only found in North America, Lindgren hopes it stays here. "It would be a shame if the third most complete specimen, with possibly the finest skull, went to another country," he said.

"A specimen like this, it needs to be seen by everyone. It's just spectacular."

Images: Craig Cutler

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