Security Machins on Cover - does anybody collect in a specialised way?

Like many collectors I put covers aside 'for later'.  One area that I thought would be good to make a collection of was the Machin definitives with the different security codes indicating source and year. 

As you probably know, some sources are encountered a lot more frequently than others.  The most common stamps found on social and business correspondence are from booklets of 12 and business sheets respectively.

From personal experience and a few reports, the least likely 2nd and 1st class stamps to be found on social correspondence are actually from counter sheets, with most people buying their stamps at supermarkets, newsagents and other outlets.

 

Inland special delivery solo use.

Displaying your collection

97p to Ukraine returned to sender.

In the case of airmail values and premium services as shown here, displaying the item in a collection is easy. The purpose is obvious and, maybe by the inclusion of a photograph, the year code can be demonstrated, this isn't as straightforward for 1st & 2nd class stamps.

 

Numbers of variants
At the time of writing there is a huge number of 2nd class blue: 13 counter sheet, 13 MTIL, 13 MBIL, at least 6 MRIL, and even more 1st class because of two types of books of 6.  And that's without any specialist variations.  Even the stamps look 'all the same; on a page in the stockbook.

To display these to members at the local club in any meaningful way would mean also including enlargements showing the iridescent printing of the year code and/or source code.  This would involve a lot of work (45 for the 2nd class) and, I think it's fair to say, while such a display might meet with surprise (as do similar displays of a year's special issue 1st class stamps) I don't think it will be very interesting.

So I have decided that, apart from my own specimens of 'one of each stamp' and any other covers showing usage, which will not be focussing on actually which of the 45 stamps it might be, I am going to abandon my accumulation.

Your chance!
Before I consign the many covers, sorted by year and source and unsorted, to kiloware I am giving readers who would like to fill gaps in their own collections the chance to do so from what I have.  I'm not going to list them - the Checklist can also be used to mark off which you have on cover if you are so inclined.  

So if anybody wants to fill a gap let me know what you need and as I work through several boxes I will set aside covers to fill those gaps.  All will be 'collectable', that is they will have dates as clear as I can get and be clean, though addresses may be handwritten.  The only charge for this will be for postage - anything else you wish to pay will be appreciated.  Any overseas collectors who have airmail-stamped GB covers - we may be able to arrange exchange and no money need change hands!

Please contact me by email.  I'll acknowledge each request and spreadsheet the requirements, which will be served in order of receipt.  It's very much a 'first come first served' opportunity.  

And it won't be a quick turn round: emptying boxes and packets will take time, probably well into the spring of 2022.  But I will do my best to provide gap-fillers if I have them.  

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