12 Maravedis - Felipe IV countermark

The 1641–1642 countermark campaign was a fiscal emergency measure, not a minting operation. Facing chronic shortfalls from the costs of the Thirty Years' War and the ongoing Portuguese and Catalan revolts, the Spanish Crown ordered existing vellón coinage restamped and revalued upward rather than strike new metal — a faster and cheaper way to extract more nominal value from the existing money supply. The countermark effectively doubled or tripled the face value of the host coin overnight.

This kind of forced revaluation bred immediate distrust and widespread counterfeiting of the punch itself.