71/2 Reales - Philip IV

The 7½ reales denomination is one of the stranger artifacts of colonial Spanish monetary administration — created not by design but by necessity, as Potosí's assayers were caught systematically debasing the silver content of macuquinas circulating across the Atlantic world. The scandal, uncovered around 1649, implicated mint officials at the highest levels and triggered a sweeping royal investigation that ultimately led to executions, dismissals, and a complete reorganization of the Potosí mint. These pieces were struck during the crisis window itself, before corrective measures took hold.

The odd denomination exists because reminted underweight 8 reales pieces couldn't be brought back to full standard without additional silver — the fractional value reflecting the actual recoverable metal.