10 Zlotys Tadeusz Kościuszko, Trial Strike

This is a trial strike — a production test piece, not a circulation issue — made as part of the extended design and alloy evaluation process that preceded Poland's 1960 coinage reforms under the Polish People's Republic. Trial strikes from this period were produced in multiple metals simultaneously, which accounts for the aluminium composition here; the circulating 10 Złotych Kościuszko type was ultimately issued in copper-nickel. Surviving aluminium examples reached collectors almost exclusively through the state numismatic agency Numizmatyka, which held a near-monopoly on official sales to foreign buyers throughout the communist era.