Lot 279
1864 (April 17): Rivadavia 15 c. blue, imperforate example from the first printing with 'RA' watermark, a fine used example with large margins all round, lightly cancelled by 'Correo Nacional de Rosario' oval in blue. A very rare stamp. Cert. RPS (1981) Gi 15 = £ 4'500/Scott 10 = $ 6'500.
