1 Ducat - Ferdinand I Klagenfurt

Ferdinand I consolidated Habsburg control over the Austrian hereditary lands following his brother Charles V's abdication negotiations, but his coinage authority over individual duchy mints remained a persistent administrative friction point. Klagenfurt's mint was among the less prolific ducal operations, making 1555 issues genuinely scarce relative to the Vienna and Hall productions that dominate surviving Ferdinand I gold. The .986 fineness conforms precisely to the ducat standard formalized at the 1524 Reichsmünzordnung, which Ferdinand himself helped enforce across his territories.