1 Thaler - Frederick I Test of Alchemy

Frederick I of Saxe-Gotha-Altenburg was an active patron of alchemical research, funding laboratory work at Gotha in the persistent seventeenth-century hope of transmuting base metals into silver and gold. This thaler was struck specifically from metal claimed to have been produced — or at least refined — through alchemical process, a practice the German courts called a Probationsthaler or trial piece. Whether the metal was genuinely of alchemical origin or simply repackaged refined silver was, then as now, largely unprovable.

Such pieces were minted as much for political theater as metallurgical proof, circulated among peer courts as demonstration of a duchy's scientific ambition.