Where can you buy a Triceratops skull?

A Christie's employee poses next to a Triceratops skull at Christie's Auction House in London, Aug. 5, 2013.

The skull, which was excavated in the U.S, makes up part of the "Out of the Ordinary" sale at Christie's.

A brass sculpture of a Rhinoceros sits at Christie's Auction House in London, Aug. 5, 2013, as part of the upcoming "Out of the Ordinary" sale.

A visitor looks at items for the upcoming "Out of the Ordinary" sale at Christie's Auction House in London, Aug. 5, 2013.

Elial Lemanski, 4, sits under an oversized chair in the shape of a stiletto at Christie's Auction House in London, Aug. 5, 2013.

Riva Lemanski, 6, sits on an oversized "Mademoiselle" chair at Christie's Auction House in London, Aug. 5, 2013. The chair, by Finnish designer Ilmari Tapiovaara, is part of the "Out of the Ordinary" sale at Christie's.

A Christie's employee poses next to "Cygan," a giant robot at Christie's Auction House in London, Aug. 5, 2013.

Riva Lemanski, 6, sits on a giant rocking horse chair outside Christie's Auction House in London, Aug. 5, 2013.

Children Riva (left) and Elial Lemanski turn the blades of a Rolls Royce fan at Christie's Auction House in London, Aug. 5, 2013.

A Christie's employee poses next to a Triceratops skull at Christie's Auction House in London, Aug. 5, 2013.

The items listed in Christie's "'Out of the Ordinary" sale will be auctioned in early September.