Triceratops skull named Sophia, valued at $600,000–800,000, goes to auction in the US with a starting price of $360,000

Sophia is a juvenile, that is, an individual incapable of reproduction at the time of death. Her skull, about two metres long from snout to frill, was recovered five years ago from the Hell Creek Formation in North Dakota. The same site yielded the skull of a pachycephalosaurus, recently bought by the National Museum of Natural History in Washington, and another triceratops, sold for $5.4 million in November.

The seller maintains that the skull is assembled from the bones of a single animal, without additions from other people's fragments, which considerably increases the rarity of the piece. Its preservation, at around 60%, is also quite good. But do you know what the trouble is? Sophia has not yet been published or studied, which means that a scientifically undescribed specimen will most likely vanish into private hands and be closed to research in the future.