Subject:
During an exhibition of philatelic material at the Royal Philatelic Society London on 24th October 2025, Steve McGill FRPSL presented an overview of the Machin definitive series of Great Britain postage stamps. The presentation focused on the driving aspects of the stamps that have produced over 7,000 catalogued varieties. The presentation was accompanied by three exhibits covering the development of postal mechanisation in the United Kingdom that explained the complex origin of the series’ phosphorescence varieties; the denominated printings and Non-Value Indicated printings. The series possibly represents the most reproduced image in the history of printing. The presentation covered a range of printings from archival material to the cutting-edge 2-D barcode stamps and touched on the artistry, printing processes, phosphor/fluor, paper & gum, perforation and security techniques. A discussion of catalogues and material availability was included, and the series is particularly notable be