GIBRALTAR 1898 4d imperforate colour trial in violet and blue-green, SG43Gibraltar 1898 (13 July) 4d imperforate colour trial in violet and blue green, watermark CA, SG43. Brilliant mint example with large part original gum. This comes from the series of 20 4d colour trials prepared by the printers, De La Rue to enable colour selection for the 2d, 4d, 6d, 1s values in the forthcoming Sterling reissue set. Attractive and very rare. Only one complete set of 20 survives intact. Representative single examples, such as this,