As far as I can ascertain, the first stamps to be printed using this new type of "dead paper" was the re-engraved high value 'castles' featuring a gold head and for the first time incorporating an eliptical perforation on either side of each stamp as an additional security measure.
The original high values printed on fluorescent paper and coatings was issued on the 18th of October 1988 with the new 'gold head' stamps replacing them on 24th of March 1992.
Here is a view of the two types of £1-50 stamps under normal light. >
The difference in the type of paper can easily be seen once subjected only to long wave ultraviolet light. >
In using this new type of "dead" paper to print stamps, the fluorescent contaminants found in some of the papers used previously would now be completely eliminated in respect to future printings, along with the problem of fluorescent coatings that had apparently been found to be fugitive, this new type of paper solved two long outstanding problems that had been previously encountered, and also gave uniformity in the quality control of things that was previously lacking on paper issues in the past.
Therefore any paper variations such as the differing fluorescences and coatings or actual base papers previously used, including contaminants can no longer be found due to the use of this new type of paper for the printing of stamps.
Having said that, over the years up to this changeover of paper there has been many variations produced, some of which have yet to be discovered and are possibly unrecorded as far as catalogue listings are concerned, the problem may have been resolved, but many stamps exist in varying degrees and condition prior to the change over to the"dead" paper being introduced from 1992 onwards.
Here is another stamp for consideration.
The 24p Chestnut on PCP
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To add to the ever increasing quantity of stamps discovered that have been printed on a contaminated paper, I can now show you the 24p chestnut shade aka rust, printed on a phosphor coated paper that was first issued on the 10th of September 1991, the first attachment being taken under long wave ultraviolet light >
The second attachment is a mono version of the same stamps >
Here is a greater abundance of them due to the fact they were getting more common as time progressed, is it any wonder that the paper was changed in 1992
More of the little tykes including booklet stamps >
Another stamp to be found on contaminated paper is that of the 24p pictorial depicting winter time as the new type of paper had not yet been introduced on a permanent basis >
Quantities of the contaminating fibres (snow flakes) will obviously vary somewhat, mainly due to the inconsistent amounts of some of the contaminated rags used during the papers production whilst in the pulp stage.
Therefore any Machins printed on or before early 1993, wether they be commemoratives or definitives have a possibility of having paper variations similar to the ones already previously described.
According to specialised catalogues via information received from the GPO, 1962 marked the beginning of the production and issue of whiter papers only to print the multiple crown Wilding stamps and according to this information whiter paper stamps would be printed from then on.
Having looked at several values I am now beginning to wonder if this was the case, as the next three attachments does not seem to conform with the information given by the GPO at the time.
This first attachment shows 2 X 5/- "Castles" one apparently printed on a cream paper, whereby the lower one is on a whiter paper and below the 2 X 5/- stamps are 6 X 5d values each stamp appears to have been printed on a cream paper but were all cancelled in 1964 as can be seen in the next attachment. >
As seen in the normal spectrum. >
I have heard of late usage with some stamps but two years seems to be an exceptionally long period of time for the cream papers to have been used and from different areas of the country.
And finally, using the same stamps but observed from the reverse one can see the difference between the whiter paper of the lower 5/- value and the 6 X 5d values underneath >
WM.