A rare elephant bird egg was among the more unusual lots to sell at Christie's Interiors: Style and Spirit auction on May 22 in London.
Estimated at £10,000-15,000, the pre-17th century, 12.5-inch high specimen sold for £12,500 ($19,763).
The elephant bird, a native of Madagascar, could grow to twice the height of a man and was the largest bird to have ever lived. It was capable of producing eggs 160 times larger than those of a chicken. It became extinct in the 17th century.
The auction follows the $53,125 sale of another elephant bird egg at Heritage Auctions on May 20, evidence that the market for these unusual specimens is strong.
The Christie's auction also featured a pair of double curved woolly mammoth tusks, which sold within estimate at £15,000.
The 55-inch specimens once belonged to a mammuthus primigeniu and have been dated to between 110,000 BC and 10,000 BC,
"Dark in colour, apparently due to the diet of this particular mammoth, a complete pair has not been offered at Christie's in recent memory," the auction house commented.
Mammoths died out in around 1,700 BC. A single tusk sold at Christie's in September 2011 for £7,500.
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