Lot 70505 – 1912-13 £1 Colour trial in yellowish green in a deep shade, a stunning mint nh corner marginal block of six

1912-13 £1 Colour trial in yellowish green in a deep shade, a stunning mint nh corner marginal block of six from the lower left of the sheet from the experimental printing on Joyson paper each overprinted “Cancelled” type 24, the selvedge at foot showing part of the “Postage” watermark inverted, fresh beautiful colour, a major Seahorse issue rarity, ex NPM archives (SG £19’500 as singles).