1 Mark on 30 Pfg overprint issue with bright lilac gray burelage, tips downward, variety "double burelage", date-appropriate cancelled "Schoenbaum . . . 10. 21", except for a little compressed perforation left in perfect condition, photo expertize Soecknick BPP (2017) : "genuine and immaculate", Michel 1. 500.- - very rare stamp!