1 Peso

The two watermark variants documented for this note — one with thin dark lines running through the upper portion of the numeral, one without — reflect an unplanned inconsistency in the paper stock supplied to Casa de Moneda rather than a deliberate design change. The distinction is subtle enough that it passed through quality control unremarked, and both types circulated simultaneously.

Issued in the immediate aftermath of the 1955 coup that ousted Perón, the note predates the major monetary reforms of 1969–1970 that would eventually retire this peso entirely.