Sorting High Values

Hi Roy

Many thanks for describing the High value recess printed stamps (25/02/07). Can you explain how do I tell the difference between Contractors paper and Post office paper ? I am also confused / having trouble sorting the 50p values printed on Phosphor Coated Paper. Also if possible more information would be helpfull regarding the £1 values and cross hatch design.

I hope you can help.

Hi James .

Thanks for your your email. My internet post bag is getting larger by the day, at least is shows that some people are reading this blog. Please continue to do so and recommend it to your fellow collectors, in return I will do my best to answer these questions.

There is no easy way to describe these issues in laymans terms. It is recommended when separating these issues to use a short wave Ultra Violet light for phosphors and a long wave for papers. (UV lamps are described in an earlier post)

Post Office papers / Contractors Papers

( 17/06/70 ) when viewed under the light this is comparatively dull in the margins compared to the Brightness of (Bradbury Contractors Paper) 30/11/73. If in doubt use a pre decimal 2/6, 5/- or 10/- value to compare, these are on dull paper.

PCP

The 10p value only exists on phosphorescent dull Post Office paper. The use of this paper was due to a continued experiments with AOP to provide information to the boffins as to what weather conditions would place upon the phosphor when stamps were printed in recess.

All over Phosphor paper or Phosphor Coated paper as it has come to be known, has an all over after glow under short wave UV light. Use the 10p value as a base template to compare with the 50p values on PCP. Again this 50p was printed on dull Post Office paper 01/2/73.

As with the 10p value, the AOP stamp has an all over after glow under short wave UV light. This was printed on the residue of paper left from the 10p printing. Earlier 50p values were on normal (dull) Post office paper without phosphor or an after glow.

20p , and later printings of the decimal £1 values can be found on both contactators and post office paper without a phosphor coating.

Early printing of the £1.00 value with the original pre decimal £ sign can only be found on Post office paper. Later ( FIRST) printings (1970) decimal issue with the old type £1 sign were printed on new plates, these were made up from the same master die , but the settings changed to a single pane of 100 (10 x 10 ) in place of the original plates of 4 panes of 40 ( 8 x 5 ).

To recognise single copies of the decimal issue from pre decimal one must use a high power magnifier or microscope and study the background shading. Top left and bottom right corners are the best to study and compare. If in doubt again compare the new £1 script under magnification with a 2/6, 5/-, or 10/- value.

The pre decimal print has thicker horizontal lines of shading and the none engraved area to the eye looks like square white patches, the decimal printing has thicker horizontal lines of shading and the none engraved area shows up as white vertical boxes.

If you are still unsure, about the £1 differences, purchase a plate block, look for plate 3, these are distinquishable from plate 3 of the pre decimal printing in the fact the decimal printings show part of the TOTAL SHEET VALUE IN THE MARGIN opposite R9/10.

I hope this helps you in your quest to sort and understand these issues more.