Lot 50055 – Great Britain – 1880 2s Queen Victoria: group of five glass clichés

Great Britain – 1880 2s Queen Victoria: group of five glass clichés of the position « KJ », four illustrating differing levels of light exposure which have manifested in varying ranges of image quality as well as colour intensity from a faint sepia, silver grey, light brown and brown, one annotated first attempt with 2 minutes exposure, another as the second attempt at 1 minute 30 seconds (« 2′ » and « 1’30 »), and a further glass cliché with a stronger impression in a dark brown shade; this group clearly shows the deliberate process Sperati followed in timing the reaction of the chemical products to establish the most desirable outcome; this is the first time such are offered at auction.