Szeląg - Jan II Kazimierz Waza Wilno mint

The Wilno szeląg issues of Jan II Kazimierz span one of the most catastrophic decades in Polish-Lithuanian history — the period known as the "Deluge," when simultaneous Swedish, Russian, Transylvanian, and Cossack invasions gutted the Commonwealth's treasury and administrative capacity. That small-denomination coinage was produced at all during these years is itself notable. The Wilno mint operated under severe pressure, and quality control across the run is inconsistent enough that die varieties within the Kop#3581–3587 range differ meaningfully in workmanship.

Copper szelągi were introduced in 1659 precisely because silver supplies could no longer sustain even this modest denomination.