Airmail cover sent to Buenos Aires on 20/MAR/1951 franked with 32c., datestamped in GRAL. SAN MARTÍN Antarctic station, VF quality (Image)

Cover sent from Matienzo Antarctic station to Buenos Aires on 7/DE/1964, franked with the 3 values of the "Orkney Islands" set, along a cinderella "Las Malvinas son Argentinas", VF quality (Image)

Cover sent to Rio Gallegos on 6/FE/1965, with cancel of MATIENZO Antarctic station, and printed mark of "Operación STAM 500/501 Primera Línea Aérea Regular Rio Gallegos Base Matienzo", VF quality (Image)

Cover commemorating the "Operación 90" expedition to the South Pole, signed by Cnel. Jorge Leal, chief of the expedition, VF quality (Image)

11 Covers used between circa 1955 and 2000, all with CINDERELLAS, VF quality (Image)

28 Covers used between 1998 and 2016, franked with commemorative stamps, VF quality (Image)

Circa 1926: Buenos Aires - Switzerland, cover franked with 3c. Post Centenary strip of 3 + 4c. San Martin w/o period block of 4 (total 25c.), VF quality (Image)

Folded cover sent to the "Consul of the King of Italy in Buenos Aires), franked with 5c. Escudito w/o accent worn plate (GJ.14) with immense margins, straightline blue FRANCA cancel, and Rosario backstamp of 29/JA/1864, excellent quality (Image)

1/AP/1867: Chivilcoy - Buenos Aires, folded cover franked with 5c. Rivadavia 4th printing with PARTIAL DOUBLE IMPRESSION variety (very notable, in over 50% of the stamp), with ellipse "ADMON DE CORREOS DE CHIVILCOY" cancel, VF (Image)

10/JUL/1875: Buenos Aires - Bordeaux (France), folded cover franked with 10c. Belgrano (GJ.39), VF quality (Image)

2c. Kidd lettercard sent from Buenos Aires to San José (Costa Rica) on 1/JA/1889, due marking, with transit marks of Rio de Janeiro and St. Thomas, VF quality, VERY RARE DESTINATION, possibly the only Kidd lettercard sent to this country! (Image)

1891: Buenos Aires - Madrid, 5c. stationery envelope uprated with 3c. Juárez Celman perf 11½x12 (GJ.124), total postage 8c., VF quality (Image)

5c. Stationery envelope sent to Buenos Aires on 5/AU/1891, with rectangular datestamp of CHACABUCO (B.A.) along "9" mark, VF quality (Image)

6/JUL/1892: Buenos Aires - Madrid, cover front with pair 6c. Sarmiento (GJ.108), VF quality (Image)

21/FE/1893: Devoto - Córdoba, 5c. stationery envelope, backstamped "CARTERO N 10 - CORDOBA", VF quality (Image)

4/JUN/1893: Buenos Aires - Toronto (Canada), 5c. stationery envelope uprated with 1c. and 3x 2c. Rivadavia (total 12c.), with "BUZON 84", New York transit and Toronto arrival backstamp, VF quality (Image)

Cover sent to Genova (Italy) on 25/DE/1893, franked with 12c. Belgrano, with oval datestamp of TRENQUE LAUQUEN (Buenos Aires), VF quality, rare (Image)

Mourning cover sent from Buenos Aires to Sistri Levante (Italy) in FE /1891, franked with 2x 3c. and 2x 5c. of Sudamericana issue (total 16c.), VF (Image)

5c. Stationery envelope sent to Buenos Aires on 29/OC/1895 with oval datestamp of ARROYO CORTO (Buenos Aires), VF quality, rare! (Image)

1896: Buenos Aires - Genova (Italy), registered cover franked with 40c., VF quality (Image)

Registered cover sent from Buenos Aires to Leipzig (Germany) on 13/MAR/1896, franked with 53c., VF quality (Image)

3/DE/1896: Buenos Aires - Leipzig, cover franked with 3c. Rivadavia strip of 3, VF quality (Image)

Circa 1900: Buenos Aires - Italy, registered advertising cover franked with 2 pairs 12c. Seated Liberty perf 12¼, VF quality (Image)

5. Lettersheet (Memorandum postal) illustrated inside commemorating the visit of the President of Brazil to Argentina, uprated with GJ.222 + 241 (2c. Liberty with PERFORATION 12), sent from MENDOZA to Germany on 20/NO/1900, postage dues mark for insufficient postage, VF! (Image)

PC sent from Buenos Aires to Leipzig (Germany) on 19/JA/1902, franked with 6x 1c. and 3x 3c. Seated Liberty (total 15c.), VF quality (Image)