1859, 1p ("In Ps") Blue. Unused original gum, top left CORNER MARGINAL COPY showing ink markings from the edge of the plate. THIS SUPERB GEM WITH ITS HUGE CORNER MARGINS IS BY FAR THE MOST SPECTACULAR SINGLE BARQUITOS IN EXISTANCE. Illustrated in the Kneitschel 1974 catalogue on page 104 and described as the only known corner copy of a Barquitos. In the Siegel sale of the "Islander collection" in 2008 a much less spectacular single showing only a sheet margin at left sold for 10.000 USD (including the auction fees). Certificate Brian Moorhouse (2009). (Image)