Lot 30429 – 1959 Wildings 3d deep violet “Dollis Hill phosphor trial” perforated pair, with 4mm blue phosphor centre band left and 2mm blue phosphor centre band on right

1959 Wildings 3d deep violet “Dollis Hill phosphor trial” perforated pair on gummed Crowns watermarked (upright) paper, with 4mm blue phosphor centre band on the left stamp and a 2mm blue phosphor centre band on the right stamp both printed over the ink, small spot on the gum, very fine (SG Spec. ST7(3)a/e, £675+)