1/2 Groat półgrosz - Sigismund II August (1st eagle)

Sigismund II August began issuing coinage in his own name from Vilnius while still a grand duke under his father's sovereignty — a politically delicate arrangement that made these early Lithuanian issues distinct from the Polish royal series. The "1st eagle" designation separates this type from later die variants by the specific rendering of the heraldic eagle, differences fine enough that Kopicki catalogued them across three separate numbers. Billon at this fineness was already a debased compromise, reflecting the chronic silver shortage that plagued Lithuanian minting through the mid-sixteenth century.