An envelope sent to me by a Korean stamp dealer showed me something I hadn’t thought about before: the exact same stamp with different perforations. The envelope comes with four different souvenir sheets related to (philatelic) exhibitions, the Word Fair EXPO 93 in Taejeon in 1993 and the international philatelic exhibition known as PhilaKorea in 1994.
Besides the stamp sheets there are also a few stamps on the envelope. These stamps happen to be the same stamp as in one of the sheets. It is the KPSC1516, one of the three 130 won values for which both souvenir sheets and normal sheets were printed.
With the souvenir sheets something went wrong with the perforation. This was very common with Korean stamps, somehow KOMSCO had a serious problem with their perforation machines. It is an effect visible both on postage stamps and on Korean revenue stamps. Often it is even a regular occurrence in itself (as in: exact same perforation problem), but this is not always the case. Notice the effect, such as “dancing lines” of perforations, in these PhilaKorea souvenir sheets:
This leads to a Korean postal history question. Which form of perforation would have been more common at the time when looking at postally used stamps: the bad ones from the souvenir sheets and/or booklets or the good ones from the regular stamp sheets? Next time I am in Korea I might have a look at what postal history from the 1990s is on offer at the stamps shops.