Top 10 Most Expensive Auction Items

Auction house Sotheby's announced Sept. 9 that it will sell a rare John James Audubon tome, Birds of America, and expect it to fetch between $6.2 million and $9.2 million — making it the world's most expensive book. Only 119 copies of the bird book — most of which exist in museums and libraries — remain. Here's a look at some other pricey auction items