50 Pesos

El Banco Nacional was one of several Colombian private banks operating under the 1871 banking law, which permitted chartered institutions to issue their own notes before the state eventually monopolized currency production. The American Bank Note Company handled the bulk of prestige printing for Latin American issuers in this period — their New York shop was the default choice for any institution that wanted engraved intaglio work and didn't want to rely on European firms.

The PS prefix in the Pick numbering places this squarely in the State/Provincial category — Colombian private bank issues are notoriously difficult to attribute precisely, and surviving 1883 dated examples from Banco Nacional are uncommon enough that auction appearances remain infrequent.