Priceless Sheet Of World's First Stamps, The Penny Black, Leaves UK For First Time

LONDON, ENGLAND - MAY 25: Senior Conservator, Jackie Coppen, inspects a priceless sheet of the world's first stamps, the Penny Black, prior to them leaving the UK for the first time at The Postal Museum on May 25, 2016 in London, England. A priceless sheet of the world's first stamps, the Penny Black, is set to leave the UK for the first time today. The sheet is one of only a handful left in the world, all of which are housed at The Postal Museum in London. The 176 year-old stamps - normally stored in a secure humidity controlled, alarmed vault - are so rare that they are being transported under armed escort in a specially designed bomb-proof briefcase. The briefcase has also been fitted with sensors and shock alarms to allow the Museum to check on the condition of the stamps throughout their journey. Once landed, they will be put on display at the World Stamp Show in New York, which happens just once every 10 years and is expected to welcome a quarter of a million visitors. After the show, the sheet of Penny Blacks will go on permanent public display for the first time when The Postal Museum opens its doors in spring 2017. (Photo by Miles Willis/Getty Images for The Postal Museum)