20 Zlotys COMECON Anniversary Trial Strike

COMECON — the Soviet-led Council for Mutual Economic Assistance — marked its 25th anniversary in 1974, and several member states issued commemorative coinage. This piece is a trial strike, meaning it never reached circulation; Mennica Państwowa produced such essais to test dies and assess striking characteristics before committing to full production runs, and Polish trial pieces from this period occasionally differ from approved types in alloy or finish. The distinction between ParM#P302b and the sibling P302a variants typically comes down to metal composition or edge treatment.