40 Centimos de Escudo - Isabel II

Isabel II's silver fractional coinage of the 1860s was a direct product of the 1864 monetary reform that aligned Spanish currency with the emerging Latin Monetary Union framework, though Spain would not formally join until 1868 — the same year Isabel was deposed and fled to France following the Glorious Revolution. These coins thus bracket a reign in terminal decline, struck through years of constitutional crisis, military pronunciamientos, and a treasury chronically emptied by colonial expenditure and court excess.

The .810 fineness is specific to this reform period and was abandoned almost immediately after Isabel's fall.