1880-81 Provisional Issue and 1881 1d Lilac. 1880-81 5d indigo mint n.h., very fine and fresh (S.G. £725 for n.h.) (Image)

1901 1d. die proof of issued design in black on glazed card (60 x 90mm.) marked "AFTER STRIKING" and dated "22 JAN 01" in blue, additionally initialled and dated. Scarce. (Image)

1881 1d perforated colour trial in greenish-slate on pink, very fresh, attractive and rare (S.G. from £3'000). (Image)

1881 1d perforated colour trial in purple on pink, very fresh, attractive and rare (S.G. from £3'000). (Image)

1881 1d perforated colour trial in purple on pink, very fresh, attractive and rare (S.G. from £3'000). (Image)

1881 1d perforated colour trial in dull carmine on white paper, very fresh, attractive and rare (S.G. from £3'000). (Image)

1881 1d perforated colour trial in carmine on white paper, very fresh, attractive and rare (S.G. from £3'000). (Image)

1881 CONFIDENTIAL. "A Brief Description of Thos. De La Rue & Co's, Fugitive and Doubly Fugitive Adhesive stamp Printing Inks" leaflet including a full explanation (simply put, fugitive inks showed fugitivity to solvents and doubly fugitive to water-based (Image)