Composite Tyrannosaurus rex skeleton sold at Swiss auction for $6.2 million, less than expected

A Tyrannosaurus rex skeleton, the third to ever go to auction, has been sold by Swiss auction house Koller but fetched less than projected.

The piece sold at auction Tuesday for $6.2 million, but that figure factors in the buyer’s premium. With that subtracted, the piece was sold with a $5.37 million bid, below the lower-end projection of $5.6 million. The highest projected price for the skeleton was $8.95 million.

Compared to previous T. rex skeletons “Sue” and “Stan,” both of which have a single source and both of which sold for record sums — $8.4 million for the 1997 sale of Sue, $31.8 million for the 2020 sale of Stan — the TRX-293 Trinity has less original bone mass and comes from three distinct sites.

Where Stan was 65% original bone material, TRX-293 Trinity was only 50.17% original bone material. The composite skeleton measures more than 12 feet and nine inches in height, and 38 feet long, and was made of 293 bones from three fossil finds.

The first portion, “Garfield County 1” found in the Hell Creek formation in Montana in 2012, provided part of the bones of the head and trunk. The second portion, “Garfield County 2”, found in the same formation in 2013, contributed most of the axial skeleton as well as the pelvic region.

The third portion, found in the Lance Creek formation in Weston County, Wyoming in 2013, is the source of TRX-293 Trinity’s skull, along with vertebrae and portions of the piece’s hind legs.

The T. rex skeleton’s composite nature may have hurt its value in the eyes of buyers, although it eventually sold to an unspecified private European collector.

“It could be that it was a composite — that could be why the purists didn’t go for it. It’s a fair price for the dino. I hope it’s going to be shown somewhere in public,” Koller Marketing Director Karl Green told the Associated Press.

As with other fossil sales at auction, scientists are concerned that selling off the specimens will keep them out of the hands of researchers.

“Fossils are not, or at least should not be, considered trophies or glorified action figures,” University of Maryland paleontologist Thomas Holtz told French news agency Agence France-Presse.

Mr. Holtz also said that fashioning a complete skeleton out of multiple fossil finds is “misleading”, saying that TRX-293 Trinity “really isn’t a ’specimen’ so much as it is an art installation.”