Call it a really Old Masters sale. Tomorrow, Sotheby’s France will open its salesroom for an auction not of delicate jewels or sensitively-rendered art but of fierce bones and fossils left behind by dinosaurs, including a showstopping complete skeleton of an Allosaurus that is between 135 and 153 million years old and over 30 feet long. The 86-lot sale, which carries an overall estimate of €3.6-4.6 million (or $4.9-6.3 million), will also feature several once-warmblooded critters and an assortment of other prehistoric fare. 

It is extremely rare for an entire dinosaur skeleton to appear on the market, and this will be the first-ever auction appearance of an Allosaurus, carefully arranged for Sotheby's in a lifelike running pose, its huge mouth gaping as if ready to attack.  From an earlier era than Tyrannosaurus Rex, the predatory creature was “more agile, and a bit smaller, by about 10 feet” and possessed of "long arms, unlike T. Rex, with three large claws,” Sotheby's France paleontology specialist Eric Mickeler told ARTINFO. The beast is estimated to sell for €800,000–1 million ($1.09-1.36 million), or just a bit more than the untitled Julie Mehretu painting that sold for $1.02 million in last month's Lehman Brothers Neuberger Berman sale.

At that price, the Allosaurus may be quite a good deal. In 1997, Sotheby’s New York sold “Sue,” a brilliantly publicized Tyrannosaurus Rex, to Chicago’s Field Museum for $8.4 million. As Mickeler points out, “Sue” was still encased in rock at the time of that auction, and it took four years for the Field Museum to prepare it for exhibition after its purchase. At a Bonham’s auction last year, another Tyrannosaurus Rex was expected to fetch $6-8 million, but did not sell. 

Although institutions are a natural market for such an enormous object, Mickeler said that “for several years now in France you have important collectors who actually have the space to put such items in their home, not just natural history collectors but also modern and contemporary art collectors.” The dinosaur, he added, is “perfectly suited for a contemporary interior.” According to the specialist, “there has been demand, a real interest” since the sale was announced, with certain French entrepreneurs indicating that they may be interested in acquiring the dinosaur to give or loan it to a museum.

Large dinosaurs that are excavated tend to be granted names — “Sue” was named after archeologist Sue Hendrickson, who dug it up in 1990 — but this Allosaurus, unearthed on a Wyoming ranch in 2005-2006, has not yet been christened. The purchaser will have the right to give it a name, and will also hold all rights of reproduction should museums wish to purchase resin casts of the skeleton for their collections.

Other top dinosaur lots in tomorrow's sale include the skeleton of a Plesiosaurus, a 190-million-year-old aquatic reptile that is one of the most complete specimens in existence (est. €320-370,000, or $436-504,000), and a rare fossil of a Dorygnathus, a flying reptile that resembles a Pterodactyl (est. €162-200,000, or $221-272,000). Geological marvels are also featured, including a citrine crystal nicknamed “The Magic Flower,” and a large tourmaline crystal on a base of white albite (each est. €320-350,000 or $436-477,000).

But if mammals are your thing, don’t despair: also galloping onto the auction block are a complete woolly rhinoceros skeleton from Pleistocene-era Siberia (est. €70-90,000, or $95-123,000) and a European cave bear displayed in a setting of moss and tree trunks, a relative bargain at €20-25,000 ($27-34,000).