COLOMBIA. Lot of (2) Banco Nacional de los Estados Unidos de Columbia. 1 Peso, ND (1880). P-141. Front & Back Proof. About Uncirculated. Exquisite detail stands out on both the front and back proofs for this 1 Peso design. Both have been mounted on cardstock, with the typed date of "December 1880" at the top on the front proofs cardstock. On the back proof PMG comments "Thinning."