25 Centimes Standing Helvetia, white paper, colour variety dark to blackish opal-green, somewhat blurred print, control mark 1 X, perforated 11 3/4, mint never hinged with untreated original gum, perfect condition, unsigned, opinion Briefmarkenprüfstelle Basel (2002) "mint never hinged, sound" Zumstein 1.200.- CHF (Zumstein No. 67Ac)