Big John was found in 2014 in South Dakota by paleontologist Walter W. Stein, owner of PaleoAdventures, a fossil-seeking tour group. Stein was digging in the Hell Creek formation, an ancient fossil-rich floodplain when he struck gold. The largest triceratops skeleton ever found, Big John is in remarkably complete condition. His skull is over 6 feet wide, and his two immense horns are almost 4 feet long and a foot thick at the root.

Big John is complete enough that we even have a probable cause of death. The collarbone – as thick as a car bumper – has a deep notch in it which may suggest a fatal combat wound. He lived an estimated 66 million years ago on an island continent that geologists call Laramidia – these days, it’s the highlands of South and North Dakota, surrounded by the remains of a shallow sea that used to cover most of central North America.

Big John was put up for auction on Thursday, October 21, at a Paris auction house. The gavel dropped at $7.7 million, put up by a private collector, making Big John the most expensive fossil ever to sell in Europe.

Djuan Rivers, a representative for the anonymous buyer, said “it’s being acquired by an American collector… absolutely thrilled with the idea of being able to bring a piece like this to his personal use. The history behind this and the duration of it is absolutely impressive. So to be able to be a part of preserving something of this nature… it’s also something extremely special.”

The most expensive fossil ever sold in the world was just last year, when a complete Tyrannosaurus Rex skeleton named Stan sold in New York for a staggering $32 million.

Paleontologists have expressed concerns about the rising price of large fossils like this in auctions – they are rapidly going out of reach of museums and researchers, instead becoming show-pieces in the homes of the wealthy where they may not be properly conserved. But while Big John is unique in his size, complete and near-complete triceratops fossils are not rare – over 50 have been found in the Hell Creek Formation alone.

Image: Vladimir Bolokh /