A rare turquoise mosaic mask is displayed at The Britrish Museum on April 7, 2009 in London, England. The Aztec mask, originally from Mexico will be one of the key exhibits to go on show at the Moctezuma: Aztec Ruler exhibition which opens to the public on 24 September 2009. (Photo by Dan Kitwood/Getty Images)

Actress Emma Watson attends the World Premiere of Harry Potter and The Deathly Hallows – Part 2 at Trafalgar Square on July 7, 2011 in London, England. (Photo by Ian Gavan/Getty Images)

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)

Anglers cast lines through holes into a frozen river during an ice fishing competition at the Hwacheon Sancheoneo Ice Festival on January 7, 2012 in Hwacheon-gun, South Korea. (Photo by Chung Sung-Jun/Getty Images)

Carlos Boozer #5 of the Chicago Bulls grabs a rebound next to David West #30 of the New Orleans Hornets at the United Center on March 7, 2011 in Chicago, Illinois. The Bulls defeated the Hornets 85-77.

Cannabis cigarettes at the growing facility of the Tikun Olam company on March 7, 2011 near the northern city of Safed, Israel. In conjunction with Israel's Health Ministry, Tikon Olam are currently distributing cannabis for medicinal purposes to over 1800 people in Israel.