Tyrannosaurus rex Bone Fossil | Hell Creek Formation | South Dakota

Tyrannosaurus rex
Cretaceous (68 - 66 million years ago)
Private Ranch, Hell Creek Formation, South Dakota
Assorted sizes available

Receive ONE, random hand selected piece, each one is hand selected for quality and each piece is unique. Picture is representative of what you may receive, however actual piece varies.

These bone fragments are genuine pieces of Tyrannosaurus rex. They were recovered during an excavation of identifiable T. rex bones from the Hell Creek Formation in South Dakota.

Tyrannosaurus rex was most likely an apex predator, feeding primarily on hadrosaurs and armored herbivores such as ceratopsians and ankylosaurs, and possibly even sauropods. Like many large predators, T. rex may also have scavenged when the opportunity arose, taking advantage of virtually any available meal.

The skull and teeth of T. rex were highly specialized for delivering an exceptionally powerful, bone-crushing bite. It could exert nearly 8,000 pounds of bite force—more than twice that of the largest living crocodiles, which possess the strongest bite force among living animals. Its long, conical teeth could also generate an astonishing 431,000 pounds per square inch of pressure, allowing them to penetrate and fracture bone.

T. rex was one of the largest terrestrial carnivores to ever live. One of the largest and most complete specimens, famously nicknamed “Sue,” measured approximately 12.3-12.8 meters (40-42 feet) in length, stood about 3.66 meters (12 feet) tall at the hips, and has been estimated to have weighed between 8.4-14 metric tons.

The bones of T. rex were built for both strength and efficiency. They had a dense, hard cortical outer layer surrounding a much more porous, spongy interior containing marrow. This structure provided considerable strength while keeping the bones relatively lightweight. Because the softer, porous interior weathers away much more quickly than the dense outer layer, most of the surviving fragments are likely to consist primarily of cortical bone.