GJ.11a, 1884 1c. Little Envelope perf 12¼ with diagonal and INVERTED overprint, mint with full original gum, superb and very rare. Signed by Kneitschel on back. (Image)

GJ.20, 1884 12c. Little Envelope perforation 14¼, used, superb, extremely rare (very few known genuine examples, the catalog value is incidental). With several guarantee signatures on back, including Victor Kneitschel (Image)

GJ.558, 1931 20c. San Martín typographed with "M.O.P." ovpt., MNH block of 4 (+50%), superb! (Image)

GJ.677P, Map with Antarctica, national unsurfaced paper, IMPERFORATE corner block of 4, excellent, with light hinge mark in the sheet margin (MNH stamps), rare! (Image)