Specimen stamp

A specimen stamp is a postage stamp or postal stationery indicium sent to postmasters and postal administrations so that they are able to identify valid stamps and to avoid forgeries.The usual method of invalidating the stamps is either overprinting in ink or perforating the word Specimen across the stamp and where English is not the common language, the words Muestra (Spanish), Monster (Dutch), Muster (German) or Образец (Russian, 'Obrasetz') have been used instead.

Specimen stamp

A specimen stamp is a postage stamp or postal stationery indicium sent to postmasters and postal administrations so that they are able to identify valid stamps and to avoid forgeries.The usual method of invalidating the stamps is either overprinting in ink or perforating the word Specimen across the stamp and where English is not the common language, the words Muestra (Spanish), Monster (Dutch), Muster (German) or Образец (Russian, 'Obrasetz') have been used instead.