GJ.4, 8c., with handstamps horizontal overprint, VF (Image)

GJ.10, light mark on the gum, VF quality (Image)

GJ.16, with VARIETY: dot below the "A" of OFICIAL (Image)

VERY RARE VARIETY: GJ.16 with INVERTED OVERPRINT, very fine quality, possibly unique! (Image)

GJ.16A, 8c. claret, very rare stamp, not catalogued in used and it is possibly the only one in existence, tiny thin on back in one corner, barely visible and only mentioned for the sake of accuracy, completely insignificant. Signed by Victor Kneitschel on back (Image)

GJ.19, 12c., Little envelope, perf 12¼, very nice (Image)

GJ.28, mint without gum, VF (Image)

GJ.29, high value of the set, with light natural paper fold, VF (Image)

GJ.32, 24c. San Martín with carmine-red ovpt. (Image)

GJ.33A, 60c. with carmine-rose ovpt. (Image)

GJ.34, 90c. Saavedra, high value of the set with red ovpt., RARE and of VF quality (Image)

GJ.112, 20c. Juan Martín Güemes, block of 4, VF (Image)

GJ.119, 10c. Rivadavia, type I, block of 4 of VF quality (Image)

GJ.127, 5c. on German paper with horiz honeycomb wmk, rare (Image)

GJ.130, with VARIETY: honeycombs in the watermark incomplete, very uncommon (Image)

GJ.138, unwatermarked paper, excellent quality (Image)

GJ.157c, with VARIETY: overprint on the left, VF (Image)

GJ.185, marginal block of 4 printed on pelure paper (70 microns), crease in the top stamps, very interesting (Image)

GJ.213b, fantastic block of 4 with VARIETY: DOUBLE OVERPRINT, one inverted on front + one albina on back (without ink), very rare and much more in this premium quality! (Image)

Over 30 mint blocks of 4 with "M. G." overprint, catalog value US$150+, all stained (Image)

GJ.240/41, with multiple suns wmk, perf 13¼ x 12½, the 2 high values of the set in blocks of 4, VF quality (Image)

GJ.307, block of 20, perf 13¼ x 12½, one with VARIETY: "I" broken (produced by an ink spot), value of a normal block US$38 (Image)

GJ.307, corner block of 10 with VARIETIES: Shifted overprints + one stamp with "incomplete M" (Image)

GJ.308, large corner block of 50 with sheet number, most MNH (Image)

GJ.317, corner block of 30, most MNH (Image)