1920 5m slate and carmine, both the center and "Danzig" overprint inverted, additional variety broken "a" in "Danzig", unused with some original gum, which has been redistributed and to some extent manipulated and enhanced, minute soiling, h.r., centered to left, fine, with 2007 Sergio Sismondo certificate. Only one sheet of 20 was discovered with both the center and overprint inverted. One can argue that in this case, it is the frame which is inverted, hence both the center vignette and overprint are correctly positioned to one another. Only 12 examples of this error have been documented, this one being the only known broken type variety (according to Sismondo "unique") (Mi.15BK1, Euro 18,000+) cat. $15000 (Cat No. 15a,var) (Image)

Cat. $15000, Est.US$10,000