2017-05-29 Mon

The British Post Office are doing everything in their power to increase the security of the Machins after the first postage stamps were issued in 1840.

To put an end to the circulation of forged stamps, two large elliptical perforations were added to Machins. The Scott Standard Postage Stamp Catalogue calls these syncopated perforations.

Straight edges in booklet panes, which had been introduced in 1987, were discontinued in 1993 for the same reason.

A £1 violet Machin stamp was made public in the standard low-denomination size. It was coated with a shiny, transparent, iridescent ink called iriodin. This feature prevented counterfeiting of the stamp.

Iridescent overprints were introduced to all self-adhesive Machins in 2009 and to conventionally gummed Machins in 2013. These consist of wavy lines of the text “ROYAL MAIL.” However, the lines over the queen’s portrait have a different pattern compared to the background and denomination tablet.

A one-character alphabetic source code replaces one letter of the iridescent overprint to showcase the issue format. For example, “F” indicates a booklet of four, and “S” indicates a booklet of six.

A two-digit year code representing the year the stamp was printed replaces two letters of the overprint. However, on the stamp, the location of these codes keep on changing periodically.

There are times when to mark a special event, the text of the overprint is changed. Even the Scott catalogue provides details of the overprint but doesn’t summarise the presence of source and data codes.

Two extended oval shaped slits were added to self-adhesive stamps in 2009. This made it difficult to peel off an uncancelled stamp from an envelope. The Scott catalogue describes these as oval slits.

In spite of many efforts, counterfeit Machins are very common today and often look similar to genuine stamps. Collectors should be wary of purchasing mint Machins for unusually low prices, especially in large quantities. Kiloware containing used Machins might also contain counterfeits.