Lot 70413 – 1971ca. Harrison’s photogravure giant Machin head and background proof group

1971-80, Harrison’s photogravure giant Machin head and background proof group of proofs incl. 1) 203x254mm proof in ultramarine on OCP paper, used for the original 3p colour with stamp affixed at top left, one of only seven proofs known in this colour; 2) 203x254mm proof in phosphor ink on OCP paper with cream PVA gum; 3) 1980 « Printed for Crosfield Electronics by Harrison & Sons » proof in bright blue, 200x295mm, on FCP ungummed paper incl. photocopy of letter to Harrisons from Aubrey Walker at PO Quality Assurance Dept.; and 4) large photographic print in black and white of the Machin head, 200x250mm; a stunning group for the specialist.