Last Post for the Norvic Security Checklist: I think it's all over!

"From February 2009 1st and 2nd class Machin Definitives and higher-priced 'make-up' values at 50p and £1 will be produced as self-adhesive Stamps with enhanced security features including semi-circular slits and an irridescent overprint.

"These initiatives are part of the on-going development of security features for Stamps. The slits are designed to inhibit the removal of these Stamps for fraudulent sale and re-use. The overprint features the words 'Royal Mail' in a pattern reminiscent of security features on banknotes."

This was how I announced the introduction of Machin definitives with security features on our website back in 2009.

It was only in April 2009 that we listed the different source codes, following the report on the Machin Mania blog. This in turn reported that the late Douglas Myall had written that 'the non-denominated security Machins have a hidden code that identifies the format in which the stamp was issued'.

The following April, the late Alec Withell reported that new retail booklet stamps had a year code, and this was soon found to apply to all stamps printed each year.  There were inconsistencies, with many new years' printings not being sold until the following year - but occasionally in the previous year!

Catalogue producers then had to work out how to list these new stamps with their variations.  Gibbons, sadly, chose a complex way of doing so.  There is a logic to it, but their system caused multiple changes, such as for the Recorded Signed For stamp is listed as

Concise 2010: U2916a;
Collect British Stamps: U2940;
Concise 2011: U2981.

I had already decided on a different numbering system, and started a conversion table, in part so that users of preprinted albums with SG numbers would know where to find the stamps in our sakes listing.

This developed into the Checklist which has developed over the years, with the help of so many readers and other collectors, running to over 50 pages.

Now that the last of the Machins have been issued, there will be no more additions to the Checklist, and no changes unless somebody wants to go through and fill in all the missing printing dates etc. 

The last edition is now available for downloading here.

My thanks to friends, collectors and dealers for their continued contributions to this list over the years.

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