50 Céntimos Oropesa

Oropesa is a small coastal municipality in Castellón province, and like hundreds of similarly sized Republican-held towns during the Civil War, it faced a near-total collapse of small-denomination coinage by 1937 — hoarded, melted, or simply absent. The municipal council's solution was to print its own fractional emergency currency, known generically as "billetes locales" or "moneda local de guerra." These circulated only within the issuing municipality and were theoretically redeemable once normal coinage returned, a promise most councils never had to honor.

The square format is a direct consequence of paper economy — cutting square sheets wasted less stock than standard rectangular layouts when working with whatever card materials were locally available.