Basel. Switzerland, Canton Basel - 1845 2 ½rp, glass support cliché in black with image in reverse, showing the main design to be printed in black; a fascinating, rare, and beautiful component of Sperati’s highly sophisticated reproduction process for this world-famous stamp that required the use of three separate printing clichés plus embossing. (Image)

Zürich. Switzerland, Canton Zurich - 1843 6r, glass support cliché in black and with reversed image, type B of the five types that Sperati produced of this value; a stunning and very rare reproduction example of the first issue of Swiss philately. (Image)

Switzerland, Canton Zurich - 1843 6r, glass support cliché with reversed image with a silver grey impression of the stamp design; a scarce and radiant cliché used to manufacture by lithographic process the technically very challenging final reproduction of the stamp (which Sperati appears to have worked on between 1942 and 1953). (Image)