1902ca. De La Rue Minerva head imperforate printer’s samples, with “AFRICA/2 1/2d” duty plate, set of eight matching right marginal blocks of 4, imperforate on unwatermarked wove, in four different colour combinations (dull green and brown-orange, dull and bright purple, dull green and violet, and dull green and carmine), each on both uncoated ordinary and chalk-surfaced paper, unmounted o.g. These were produced early in the 20th century, when chalk-surfaced paper was introduced for the KEVII stamps of Transvaal and the Natal, very scarce in this form. (Image)