Most Complete T. rex Skeleton Found

Context

By the late twentieth century, commercial fossil-collecting operations had become active in the Hell Creek Formation of the northern Great Plains, where erosion regularly exposed Cretaceous-era remains. Teams from institutions and private companies routinely prospected remote badlands in South Dakota and Montana during summer field seasons, often working on private ranches under agreements with landowners. The Black Hills Institute of Geological Research, based in Hill City, South Dakota, was one such organization focused on both scientific preparation and specimen sales.

What Happened

On August 12, 1990, while her colleagues repaired a flat tire on their vehicle near Faith, South Dakota, Susan Hendrickson walked alone across the prairie and noticed three large vertebrae eroding from a sandstone bluff. She alerted the team led by Black Hills Institute president Peter Larson, who confirmed the bones belonged to a Tyrannosaurus rex. Over the following weeks the crew carefully excavated the site on land owned by rancher Maurice Williams, recovering more than 200 bones that represented over 90 percent of the skeleton. The specimen was jacketed in plaster and transported to the institute’s preparation lab.

Aftermath

The Black Hills Institute paid Williams $5,000 for excavation rights and began cleaning and mounting the skeleton at its Hill City facility. Larson publicly discussed plans for a dedicated museum to display the find alongside other Cretaceous fossils. Within two years, however, a dispute over land ownership escalated into federal litigation, as authorities argued the specimen had been taken from territory tied to the Cheyenne River Sioux Reservation.

Legacy

After a 1997 Sotheby’s auction, Chicago’s Field Museum acquired the skeleton for $8.36 million with corporate sponsorship and placed it on public display in 2000. The specimen, formally known as FMNH PR 2081 but universally called Sue, has supported extensive research on tyrannosaur growth, sensory capabilities, and pathologies while drawing millions of visitors and reinforcing the cultural prominence of Tyrannosaurus rex in museums worldwide.