Per your request, Audrius:
In addition to the "Double Center" forgery with significant shift of the centers as featured in Vygintas' post, here is a similar "Double Center" fake with lesser shift between the two centers and comments of the late Dr. Klein regarding two different printing dyes used for the two centers. As well as an additional scan of a "Double Center" Forgery with one of the centers inverted.
As any philatelic examiner and expert will tell, a stamp can not be authenticated by looking at it's picture. It has to be examined in detail, has to be held in hands, looked under microscope, UV light, etc... I have seen a great example of the famous Soviet "Лимонка" stamp where the stamp design was cut out of the cheap variety stamp and inserted into the outer field with correct perforation. Splicing of the paper could be detected only under very high magnification. And that was a very old forgery too.
Having said all that, I can not deny that Vygintas' find of the picture with the large imperforated multiple is quite intriguing! As we all see time and time again - Lithuanian philately never stops surprising us with new wonderful discoveries made almost every year!
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