Gooding #21F3. A very crude forgery. Most of the stalked pearls in the side frames touch the inner or outer curved lines of the frame. The second "R" in "CORREOS" is broken just below the top loop. The curved lines of shading round the star-ornament in top right corner of the stamp is incomplete and missing a few lines. 

The eyelid is very narrow, giving the appearance of a much larger eye than the original. The lettering in "CENT" is thinner than the genuine, giving appearance of taller letters. 

The "o" in "Po" is shaped more like a square. The chain pattern, round the outer edge of the dark central oval, is small and often broken. (Similar die as Gooding #21F4).