I recently inherited
my father's stamp collection and found an interesting piece on it.
It is a deluxe proof of a Saar 1956 stamp signed by Pierre Gandon. I sent a picture to a german auctioner and he questioned the autenticity saying that in his catalogues the engraver of the stamp is Jules Piel.
I found a discussion in another forum saying that the 3 stamps of this series were engraved by 3 different artists: Charles Mazelin, Jules Piel and Pierre Gandon. I have searched for some days and made contact with a lot of sites and foruns but could not clarify my doubts.
Do you have any information that could possibly assure the autenticity of this proof?