Rarest stamp for sale on BoB

[JohnBenn 12]

Worldwide & Collections - Stamp Album with assorted stamps - as per scan for sale in Cape Town (ID:91948023)

 

Can you spot it?

 

 

Strange that forgers don't realize the stamp should be square, and only the one known copy is missing its corners. But then it could be a cutout, or a second (real) copy is also missing its corners....who knows??

 

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