It was found by the son of Arthur Wooster who was one of the two cameramen behind the pioneering film who went on to work on nine James Bond films.
Mr Wooster, 80, and his colleague Bob Angell, 87, filmed the Queen using two cameras simultaneously at different angles before blending the footage together into a single picture.
The film covered the procession to and from Westminster Abbey, a trip to the Derby at Epsom, and rare footage of the Queen and Duke of Edinburgh on the Royal Barge on the River Thames shortly after the Coronation.
Ironically, the reason the film, which cost £3,000 to make, was never broadcast in cinemas was because the Coronation caused an explosion in popularity in television. It was the first time cameras were allowed inside Westminster Abbey.