SCG7692 - Colombia 1950s Airmail Overprint – El Mono de la Pila, TunjaThis Colombian airmail stamp depicts the famous colonial fountain El Mono de la Pila located in Tunja, Boyac. The detailed engraving shows the iconic monkey statue atop the fountain within a historic courtyard, symbolizing the citys rich heritage. Originally issued as a 60 centavos airmail stamp, it bears a later overprint changing the value to 50 centavos. Such overprints were commonly applied during periods of postal rate changes or surplus stock