Poland's Environmental Protection series of the late 1970s was an unusual exercise in state-directed conservation messaging, issued by a government that was simultaneously presiding over some of the most aggressive industrial expansion in the Eastern Bloc. Trial strikes from this series — known in Polish numismatics as *próby* — were produced in limited numbers for approval purposes and occasionally distributed through the state export agency Poltrade to foreign collectors hungry for Polish material.
The .625 fineness distinguishes this próba from the standard circulation and collector strikes, which used different alloy specifications. That variation alone is the reason this piece carries separate Fischer and ParM catalog numbers.
Poland's Environmental Protection series of the late 1970s was an unusual exercise in state-directed conservation messaging, issued by a government that was simultaneously presiding over some of the most aggressive industrial expansion in the Eastern Bloc. Trial strikes from this series — known in Polish numismatics as *próby* — were produced in limited numbers for approval purposes and occasionally distributed through the state export agency Poltrade to foreign collectors hungry for Polish material.
The .625 fineness distinguishes this próba from the standard circulation and collector strikes, which used different alloy specifications. That variation alone is the reason this piece carries separate Fischer and ParM catalog numbers.