"Luxury" seals or stamps that reach a certain value must always be accompanied by a certificate guaranteeing its perfect state of preservation and authenticity.

LUIS DEL TARRE, an expert on stamps of Spain is a member of COMEX (Committee of experts in PHILATELY) where through an exhaustive study verifies and certifies the authenticity of the stamps accompanied by a certificate that COMEX.

PHILATELY LUIS DEL TARRE  recommended that certain philatelic stamps from a private collection should  be analyzed to ensure it's authenticity and for guarantee it's owner that it is an authentic and well-preserved stamp.