A Sotheby's employee holds a rare 52.82-carat white diamond ring at Sotheby's auction house on April 12, 2010 in London, England. Price: 7 million USD. (Photo by Dan Kitwood/Getty Images)

Sir Paul McCartney and Nancy Shevell leave the Marylebone Registry Office after their civil ceremony marriage on October 9, 2011 in London, England. (Photo by Danny Martindale/Getty Images)

Festive characters perform during Harrods 26th Annual Christmas Parade on November 5, in London, England. (Photo by Steve Finn/Harrods via Getty Images)

A rider demonstrates Lighting artist Bruce Munro latest installation “Star-Turn” at a one-night event in front of the Holburne Museum on December 21, 2011 in Bath, England. (Photo by Matt Cardy/Getty Images)

Dancers of the English National Ballet perform “Strictly Gershwin” at the Coliseum on January 10, 2012 in London, England. (Photo by Ian Gavan/Getty Images)

A model walks the runway during the Craig Lawrence show at London Fashion Week Autumn/Winter 2012 at Somerset House on February 19, 2012 in London, England. (Photo by Stuart Wilson/Getty Images)

A dog and its owner perform a routine in the main arena on Day three of Crufts at the Birmingham NEC Arena on March 10, 2012 in Birmingham, England. (Photo by Dan Kitwood/Getty Images)

Katy Perry attends the European premiere of Katy Perry: «Part Of Me 3D» at Empire Leicester Square on July 3, 2012 in London, England. (Photo by Mike Marsland)