"Part of the fun of this is the deal," said Stedman Mays, a Rutgers professor and an avid jewelry collector.

The crown comes from the collection of Connie Parente, a popular Los Angeles based jewelry collector.

In 2009, a replica of Mona Lisa was pieced-together using precious gemstones by a jewelry collector in China.

Although primarily known for his glass objects, Lalique's technical ingenuity and use of a variety of materials in his jewelry - glass, horn, enamel, precious stones and crystal - won praise from both art critics and jewelry collectors.

Of the work of the three designers whose jewelry is sold under their own names at Tiffany's - Elsa Perretti and Paloma Picasso are the other two - Jean Schlumberger's is "by far the finest in the repertoire," said Amy Fine Collins, a jewelry collector and fashion writer for Vanity Fair.

Though technically incorrect, other simulated opals with various types of sparkling inclusions or shiny backings are sometimes also referred to as 'foil opals' by jewelry collectors.

"To knock off a jewelry collector?"

LYN REVSON, a jewelry collector who had pieces from her private collection auctioned at Christie's last year, did more than look at the heavy stone.