Poland's postwar monetary system was still finding its footing in 1958, and the National Bank periodically commissioned trial strikes to evaluate proposed industrial and agricultural imagery before committing to full production runs. This piece never advanced beyond the pattern stage — the design was rejected, leaving surviving examples confined almost entirely to official archives and the handful that surfaced through collector channels decades later. The Fischer and ParM references both treat it as a distinct subtype, suggesting at least minor die or finish variations exist within the trial series.
Poland's postwar monetary system was still finding its footing in 1958, and the National Bank periodically commissioned trial strikes to evaluate proposed industrial and agricultural imagery before committing to full production runs. This piece never advanced beyond the pattern stage — the design was rejected, leaving surviving examples confined almost entirely to official archives and the handful that surfaced through collector channels decades later. The Fischer and ParM references both treat it as a distinct subtype, suggesting at least minor die or finish variations exist within the trial series.