50 Céntimos Silver certificate, 'en moneda acuñada de plata'

Costa Rica's Administración de Rentas Públicas was a fiscal agency, not a bank — the fact that it issued circulating currency at all reflects the chronic shortage of small-denomination notes that plagued the country during this period. The phrase "en moneda acuñada de plata" (in minted silver coin) printed on the face was a legally binding redemption promise, not decoration, intended to shore up public confidence in paper fractional currency at a time when silver coins were routinely hoarded or exported.

ABNC printed the series during a window when Costa Rica had no domestic printing capability worth trusting for secure documents. The plates were almost certainly reused or adapted across the issue's four-year span rather than re-engraved annually.