Set of eleven IMPERF COLOUR TRIALS for the 50c value of the 'Completion of the Columbus Memorial Lighthouse' issue produced by the 'Government Printing Works, Rome'. The stamps are mounted on perforated backgrounds and then mounted on a large buff coloured sheet of archive card. Each value is printed in a different colour from the issued stamp with the final value used for the colour noted below each stamp in manuscript The card has a '5 AGO 1947' archival datestamp at top and is signed in the bottom right hand corner. A superb and UNIQUE item of the highest exhibition quality. (As SG 829/839)