Except otherwise stated, all results include the premium.
Chronology : 1987 2021
Fossils are classified in the chronology of the species.
2020 SOLD for € 3.07M by Binoche et Giquello
The allosaurus has a remarkable similarity with its much later successor the Cretaceous tyrannosaurus but it is smaller. It has all the characteristics of the most formidable predators. The claws gripped and lacerated the prey and the 7 cm long teeth were curved backwards to prevent the victim from escaping. The very tall hind legs attest to its frightening power.
An adult specimen can reach ten meters, further strengthening the likeness with a tyrannosaur. A specimen with that length and mounted 3.50 m high ready for an attack was sold for € 3.07M from a lower estimate of € 1M by Binoche et Giquello on October 13, 2020, lot 140. Three ribs have traces of wounds, certainly in a fight with another beast.
Juvenile specimens are extremely rare, perhaps because their death was often due to predators that showed poor respect for the integrity of their bones. They are interesting by the proportions of their limbs still in growth phase. The first excavation of the bone of a young allosaurus in Wyoming was performed in 2006. A juvenile allosaur 3.80 m long was sold for € 1.4M by Binoche et Giquello on April 11, 2018, lot 71. It is 60 % complete.
2007 Dracula the Allosaur and Fantasia the Stegosaur
2011 SOLD for $ 2.75M by Heritage
The techniques of discovery and excavation of fossilized dinosaur skeletons are improving, and recent findings supplement and amend our knowledge. It is a matter for professionals, of course. Wyoming is their preferred ground, for the abundance of such remains.
In spring 2007, researchers at International Dinosauria were excited by the discovery of an allosaurus, whose dentition is well preserved. As they progressed in the recovery of bones of this flesh-eating dinosaur, they make a stunning and unprecedented discovery : a stegosaurus skeleton is mingled with the bones of the allosaurus.
There is no doubt that the animals killed one another 155 million years ago. Their corpses did probably fall into a river or were quickly buried by a mudslide, and the skeletons were not dispersed by other predators of the time.
It was anticipated that the dinosaurs were fighting. Grass-eating specimens were often the losers, as already shown by the bite of an allosaurus in the neck plate of a stegosaurus. But the discovery of two skeletons together was a considerable scientific novelty.
Both fossils were sold in one lot for $ 2.75M by Heritage on June 12, 2011. The allosaurus named Dracula is 6.30 m long and 70% complete. Fantasia, the stegosaurus, is 5.40 m long and 75% complete.
2013-2014 Hector the Deinonychus
2022 SOLD for $ 12.4M by Christie's
In the mean time the carnivorous dinosaurs had not lost their domination over their territories in current day Wyoming and Montana, in a favorable environment of tropical and sub-tropical forests, lagoons, swamps, and river deltas. One of them, living during the early (lower) Cretaceous 110 million years ago, was the 3.40 m long deinonychus, a wording describing its 5-inch impaling claws.
A detailed study of a deinonychus in the 1960s led to reconsider the opinion about the behavior of the carnivorous giants, from then considered to be agile and fast in their horizontal running posture with stretched tail, so obsoleting the slow standing of the previous popular imagery. Its unusually long stretched arms were used in the attack and the large optic lobes attest for a sharp eyesight. Wrongly identified as the Velociraptor, this species became one of the star dinosaurs in the Jurassic Park franchise.
A 3 m long fossil made of 126 remaining bones was excavated in Montana in 2013-2014. Named Hector in reference to the Iliad warrior, it was sold for $ 12.4M from a lower estimate of $ 4M by Christie's on May 12, 2022, lot 57C.
Further research on the physical capabilities of the deinonychus could help to model the transition from reptile to bird through the archaeopteryx, in the Jurassic, 40 million years earlier.
2002 Horus the Pteranodon
2023 SOLD for $ 3.9M by Sotheby's
The pteranodon is a toothless variety of pterodactyls with a long backwards cranial crest. The compared ratio of wingspan and chord length leads to suggest that its flight was similar to that of modern day albatross, mostly soaring under wind with short burst of flapping.
A fossil skeleton of a pteranodon that lived about 85 million years ago in current day Kansas has been unearthed in 2002, in the discovery county of the species, in a former seabed under chalk sediments. It is nicknamed Horus by reference to the Egyptian falcon god. Its 6 m wingspan and 3 m overall length are typical of a male adult of its variety.
Horus is made of slightly more than 100 remaining fossil bones including a nearly full wing with its phalanges. Many vertebrae, most of a foot and part of the pelvis are also remaining. The fossilization of its thin bones is better preserved than usual for its species. The absent elements have been replaced by using a 3D printing technique.
The articulated skeleton is displayed with wings outstretched in a soaring position and mounted on a bronze armature rigged for ceiling suspension. It was sold for $ 3.9M by Sotheby's on July 26, 2023, lot 6.
2022 SOLD for $ 6.1M by Sotheby's
Both bipedal beasts look very similar. Slightly smaller, Gorgosaurus had the more powerful biting force and muscular legs that enabled a more speedy run balanced by its long tail.
The incomplete fossil skeleton of a gorgosaurus was excavated in Montana in 2018. It has 79 elements, the rest of it being replaced by casts for its exhibition mounting. The left side of the skull is the best preserved with its maxilla and its three bones that compose the rounded orbit. The axial skeleton is also well preserved from cervical to caudal.
This prepared specimen is 2.80 m high and 6.70 m long. The dimension of the skull is 98 x 67 x 43 cm.
This fossil was sold for $ 6.1M by Sotheby's on July 28, 2022, lot 201.
2020 SOLD for $ 32M by Christie's
We have to face the facts : the tyrannosaurus, a distant successor to the allosaurus, had characteristics much more efficient than humans, in terms of sight and smell, running speed, strength and appetite. I have no reliable data about its intelligence.
The deposits are mainly concentrated on the Hell Creek Formation, an island continent bordering Montana, the Dakotas and Wyoming. In the lifetime of the terrible lizards, it was a coastal plain filled with swamps, forests and estuaries. The sediments had been displaced by the slow rising of the Rocky Mountains down to a width of 100 m or more in which the discovery of fossils is virtually unlimited.
The distribution of the species was possibly wider, but the swamps of these Badlands originally limited the dispersal of the skeletons and provided good conditions for fossilization.
Hell Creek has been known since the beginning of the 20th century as a reservoir of tyrannosaurs. More than 50 specimens have been found.
It was an amateur prospector who discovered in 1987 the hip bones of a specimen that was given his own first name, Stan. An error in paleontological interpretation delayed the researches. The excavation required 30,000 hours of work between 1992 and 1995. This male tyrannosaurus, approximately 70% complete in mass, is one of the largest specimens, measuring 11.3 m between the muzzle and the tip of the tail.
Traces on the bones provide valuable informations on the life of prehistoric animals. Stan had lesions created by the teeth of other tyrannosaurs. His broken neck had been healed by fusion of two injured vertebrae. He ate an edmontosaurus and a triceratops just before his death. In our time he plays the stars with more than 60 complete casts for use in museums and exhibitions.
The fossil includes 188 original pieces, compared with the 350 bones of a complete animal. The skull is almost perfect. Missing elements are represented by casts. It was sold for $ 32M from a lower estimate of $ 6M by Christie's on October 6, 2020, lot 59. Please watch the video shared by the auction house.
Stan deserves a similar notoriety as Sue, the 12.3 m long male tyrannosaurus found by a lady named Sue in 1990, which was sold for $ 8.4M by Sotheby's in 1997.
1997 SOLD for $ 8.4M by Sotheby's
The bones had not been scattered. The animal had lived about 67 million years ago and probably died in a stream of water that pushed it against some obstacle.
The tyrannosaurus is the most spectacular of the dinosaurs, and Sue was the largest and most complete specimen at the time of its excavation. The skeleton is 90% complete by mass and 73% by the number of elements. The cranial fossil weighs 270 kg and is 1.40 m long and the teeth are almost intact.
The owner of the land, a member of the Sioux tribe, claimed that the team had paid him the right to take and clean up the fossil, but not the transfer of ownership. Justice follows and he becomes the sole owner of Sue. He then commissioned Sotheby's to manage the auction. Due to Sue's exceptional scientific interest, paleontologists were worried about the risk of purchase for a private collection.
Nothing equivalent had happened on the market. On October 4, 1997 the bidding was started at $ 500K. Sue was sold for $ 8.4M to the Field Museum of Natural History in Chicago.
At the time of the sale, this dinosaur had been identified as exceptional but had never been mounted. Its exhibition at the Field Museum was inaugurated in May 2000. Scientific investigations have not been interrupted. The age of the animal is estimated at 28 years, making it until 2013 the dean of the tyrannosaurs. It was 12.30 m long and 4 m high at the hips and its weight in life was estimated at about 10 tons.
The image is shared by Wikimedia with attribution to the user Zissoudisctrucker. It shows Sue in its most recent display configuration at the Field Museum.
2020-2021 Maximus Rex
2022 SOLD for $ 6.1M by Sotheby's
Maximus was a large adult specimen. Its 135 cm skull is one of the best ever discovered with 30 of the 39 bones remaining, preserved in fine details. All the tooth bearing jaw elements are present with no less than 29 teeth in various states of completeness. Most of the post cranial has been destroyed by erosion.
The pathologies include bite marks and parasitic holes plus traces from bone infections. Insect borings suggest that the carcass had not been immediately covered.
The skull displayed on an iron pedestal was sold for $ 6.1M by Sotheby's on December 9, 2022, lot 1. Its articulated assembly with jaws opened includes casts of the missing bones.
The post cranial fragments are joined to the lot. Please watch the video shared by the auction house.
The skull is the major element enabling to distinct a Tyrannosaurus Rex from the other Tyrannosauridae species which include the albertosaurus and the slighty earlier gorgosaurus.
A ferocious visitor has arrived at #SothebysNewYork! This fearsome Tyrannosaurus rex skull (named Maximus!) is one of the best and most complete of its kind ever discovered.— Sotheby's (@Sothebys) November 8, 2022
Visit Maximus in our York Ave galleries before his auction this December. pic.twitter.com/7BaoweZFGP
2023 SOLD for CHF 5.5M by Koller
This dinosaur named Trinity is made of three specimens of comparable size which were unearthed between 2008 and 2013 from the Hell Creek and Lance Creek formations in Montana and Wyoming.
Such an assembly typically requires seven to ten years of work according to the auction house. Trinity is announced as coming from a US private collection.
It is about 50 % original with 293 bones representing all body parts assembled in an overall size of 11.6 × 3.9 × 2.65 m. A traceability of the merging of the elements from the three originals is provided by the auction house. The skull length is 1.4 m from only the Lance Creek specimen. The origin of most of the teeth is not identified in the skeleton map.
2021 SOLD for € 6.7M by Binoche et Giquello
A triceratops skull excavated in Hell Creek in 2018 is 2.20 m long and 85 cm wide with its eponymous forehead horns about 75 cm long was sold for $ 500K by Sotheby's on April 28, 2021, lot 1.
On October 21, 2021, Binoche et Giquello sold for € 6.7M from a lower estimate of € 1.2M the fossil of Big John, considered as the largest known full triceratops, lot 1. It is illustrated in the pre sale release shared by Drouot.
The skeleton made of nearly 200 bones is 7.15 m long and 2.70 m high at the hip. The skull is 2.62 m long and the two major horns are 1.10 m long on a 30 cm base. The skeleton is 75 % complete for the skull and more than 60 % complete overall.
Big John had been wounded and probably killed in battle as evidenced with a severe tear below the neck, made from the horn of a similar beast. It has been discovered in 2014 in South Dakota and cleaned at the Zoic workshop in Trieste. Its displayed position ready to charge is inspired from the Wall Street Bull.