GJ.23, 1884 Vélez Sárfield 20c. rouletted, superb block of 4 (bottom stamps MNH, +50%), rare in this quality! NOTE: very interesting block showing different inclinations of the overprint! (Image)

GJ.26, 1884 Alvear 25c., beautiful block of 4 mint with full original gum, very fresh and attractive. NOTE: very interesting block showing different inclinations of the overprint! (Image)

GJ.27, 1884 Alvear 30c., very rare block of 4, mint with full original gum, signed by Victor Kneitschel on back. NOTE: very interesting block showing different inclinations of the overprint! (Image)

GJ.29, 1884 90c. Saavedra, block of 4 mint with original gum, VF quality, very rare! (Image)

GJ.33A, 1884 60c. Posadas with carmine-rose overprint, rare MNH block of 4 (+50%), VF quality, very few known! (Image)

GREAT RARITY: GJ.360a, 1915 12c. Plowman on Italian paper with horiz honeycomb wmk, block of 4 with original "M.I." ovpt. with a second added "I". All the stamps are signed by Victor Kneitschel on back, the bottom stamps are MNH (+50%), and the vertical perforation is a little separated in the top stamps. Exceptional rarity, one of the 2 blocks in existence of this variety! (Image)

GJ.425EN, block of 4 with horizontal GUTTER, very fine quality, rare! (Image)

GJ.502, 1925 1P. San Martín with large sun wmk, "M.M." ovpt., mint block of 4, 2 stamps with tiny hinge mark and 2 MNH (+50%), signed by Victor Kneitschel on back, VF and rare! (Image)

GJ.525, 1916 5c. Centenary of Independence with "M.O.P." ovpt., superb block of 4, the bottom stamps are MNH (+50%), rare! (Image)

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

GJ.562a, pair with DOUBLE OVERPRINT, one faint and inverted, MNH (+50%), excellent! (Image)

GJ.664a, 50c. Petroleum, without wmk, variety INVERTED OVERPRINT and also offset impression on back, MNH block of 4 (+50%) with sheet corner, superb! (Image)

GJ.703a + 703b, 20c. San Martín on national unsurfaced paper, block of 4, 2 with vertical LINE WATERMARK, and one of those stamps also with variety "S of SAN MARTIN deformed", exceptional combination of varieties, excellent and rare! (Image)

GJ.725a, 20P. Fitz Roy with INVERTED OVERPRINT, MNH (+50%), superb! (Image)

GJ.725a, 20P. Fitz Roy with INVERTED OVERPRINT, corner block of 4, MNH (50%), superb, possibly the best block with this variety! (Image)

GJ.750, 8P. San Martín on imported unsurfaced paper, rare cmpl. sheet of 200 stamps, a few with light staining on gum, rare! (Image)

GJ.755, 20P. San Martín on chalky paper with large sun RA wmk, cmpl. sheet of 200 stamps, a few with light staining on back, most of excellent quality, rare! (Image)

GJ.759, 25P. Quebracho tree, offset, with vertical red ovpt., cmpl. sheet of 100, MNH, superb, very rare! (Image)

GJ.774, 100P. Skier, imported unsurfaced paper, complete sheet of 50 stamps, MNH, superb, rare! (Image)

GJ.776, 50P. San Martín, cmpl. sheet of 50 stamps, most with light staining on gum, catalog value US$375, good opportunity! (Image)