LONDON, ENGLAND - SEPTEMBER 13: In the month of Freddie Mercury's 70th birthday, The Postal Museum, London comes together with the Smithsonian Institution, Washington D.C., to pair the Queen singer's prized stamp album, which is normally housed in The Postal Museum's archives - with the Smithsonian's John Lennon stamp album. The superstars' boyhood collections will be on display together for the first time at Stampex, taking place at the Business Design Centre, Islington, London. Free entry from 14th - 17th September, 2016. (Photo by Rob Stothard/Getty Images for The Postal Museum)

LONDON, ENGLAND - SEPTEMBER 13: In the month of Freddie Mercury's 70th birthday, The Postal Museum, London comes together with the Smithsonian Institution, Washington D.C., to pair the Queen singer's prized stamp album, which is normally housed in The Postal Museum's archives - with the Smithsonian's John Lennon stamp album. The superstars' boyhood collections will be on display together for the first time at Stampex, taking place at the Business Design Centre, Islington, London. Free entry from 14th - 17th September, 2016. (Photo by Rob Stothard/Getty Images for The Postal Museum)

LONDON, ENGLAND - SEPTEMBER 13: In the month of Freddie Mercury's 70th birthday, The Postal Museum, London comes together with the Smithsonian Institution, Washington D.C., to pair the Queen singer's prized stamp album, which is normally housed in The Postal Museum's archives - with the Smithsonian's John Lennon stamp album. The superstars' boyhood collections will be on display together for the first time at Stampex, taking place at the Business Design Centre, Islington, London. Free entry from 14th - 17th September, 2016. (Photo by Rob Stothard/Getty Images for The Postal Museum)

LONDON, ENGLAND - SEPTEMBER 13: In the month of Freddie Mercury's 70th birthday, The Postal Museum, London comes together with the Smithsonian Institution, Washington D.C., to pair the Queen singer's prized stamp album, which is normally housed in The Postal Museum's archives - with the Smithsonian's John Lennon stamp album. The superstars' boyhood collections will be on display together for the first time at Stampex, taking place at the Business Design Centre, Islington, London. Free entry from 14th - 17th September, 2016. (Photo by Rob Stothard/Getty Images for The Postal Museum)

LONDON, ENGLAND - SEPTEMBER 13: In the month of Freddie Mercury's 70th birthday, The Postal Museum, London comes together with the Smithsonian Institution, Washington D.C., to pair the Queen singer's prized stamp album, which is normally housed in The Postal Museum's archives - with the Smithsonian's John Lennon stamp album. The superstars' boyhood collections will be on display together for the first time at Stampex, taking place at the Business Design Centre, Islington, London. Free entry from 14th - 17th September, 2016. (Photo by Rob Stothard/Getty Images for The Postal Museum)

LONDON, ENGLAND - SEPTEMBER 13: In the month of Freddie Mercury's 70th birthday, The Postal Museum, London comes together with the Smithsonian Institution, Washington D.C., to pair the Queen singer's prized stamp album, which is normally housed in The Postal Museum's archives - with the Smithsonian's John Lennon stamp album. The superstars' boyhood collections will be on display together for the first time at Stampex, taking place at the Business Design Centre, Islington, London. Free entry from 14th - 17th September, 2016. (Photo by Rob Stothard/Getty Images for The Postal Museum)

LONDON, ENGLAND - SEPTEMBER 13: In the month of Freddie Mercury's 70th birthday, The Postal Museum, London comes together with the Smithsonian Institution, Washington D.C., to pair the Queen singer's prized stamp album, which is normally housed in The Postal Museum's archives - with the Smithsonian's John Lennon stamp album. The superstars' boyhood collections will be on display together for the first time at Stampex, taking place at the Business Design Centre, Islington, London. Free entry from 14th - 17th September, 2016. (Photo by Rob Stothard/Getty Images for The Postal Museum)

LONDON, ENGLAND - SEPTEMBER 13: In the month of Freddie Mercury's 70th birthday, The Postal Museum, London comes together with the Smithsonian Institution, Washington D.C., to pair the Queen singer's prized stamp album, which is normally housed in The Postal Museum's archives - with the Smithsonian's John Lennon stamp album. The superstars' boyhood collections will be on display together for the first time at Stampex, taking place at the Business Design Centre, Islington, London. Free entry from 14th - 17th September, 2016. (Photo by Rob Stothard/Getty Images for The Postal Museum)