What is a proof? Gustamps explains.
Before stamps are printed the printers prepare a proof as an example of what the final issued stamp would look like. Gustamps explain that these proof stamps are often imperforate although the final issued stamp may be perforated. Sometimes proofs are not exactly printed in the issued colours as final colours may not have been approved. Gustamps say that occasionally they are overprinted "specimen", "proof" or "sample." Gustamps point out that if they are printed in one colour they may be progressive proofs. According to Gustamps, progressive proofs are one stage before final proofs. Proofs and progressive proofs are available for sale at Gustamps shop in Brighton.
