How do we sort the forgeries from the genuine items?
Comparison with known, genuine stamps is one of the key features. However, many of the most difficult and growing problems are the extremely skilful alterations to genuine stamps. This can range from added margins, faked or improved perforations, repairs to damaged portions of the stamp, and stamps being added to covers to which they did not originally belong. Many of these require not only a keen eye, but knowledge of printing and papermaking methods, knowledge of obliterations, and postal history knowledge in order to identify routes and rates.
The Expert Committee is assisted by the use of sophisticated equipment such as the VSC 6000, the video spectral comparator, which allows comparison of the optical properties of inks to identify forged overprints, faked colours and faked or altered postmarks.