Great Britain SG#949/996 1974-1975 Commemoratives, A Group of 29 Mostly VFNH Sheet Margin, Traffic Light and Cylinder Blocks
A mostly VFNH group of 29 different corner blocks, all selected for different marginal markings, giving some insight into the markings put in the sheet margins by Harrison and Sons during this period. Markings include a number of trafic light colour guides, cylinder numbers, colour registration markings and "Total Sheet Value" inscriptions. A nice addition to a specialized collection, as GB sheets are generally too large and unweildy to display in any album. The blocks cover the commemorative issues from 1974 and 1975, with the stamps being printed on different types of paper, giving different fluorescent reactions under UV light on the front or back, as discussed below.
Gibbons cat for just the basic stamps is between 60 pence and 2 pounds a block. Our estimate for the entire lot is $25. The blocks offered here grade between 70 and 84. There may be a few minor selvedge creases here and there, and some blocks may be folded between the perfs in places, but these do not detract significantly.
A Note About Paper used by Harrison & Sons in the 1971-1990's Period
The stamps during this period are printed primarily by Harrison and Sons by photogravure, with some issues being lithographed by House of Questa into the 1980's and later by Walsall and Enschede. Harrisons used three different types of white coated paper and two different types of gum, which were introduced over the life of the commeorative issues, and it is possible that issues that were current during the transition from one paper to another may exist on more than one type of paper, and with more than one type of gum. The three types are:
- Original Coated Paper (OCP) - The original coated paper has a slightly off-white appearance and the gum is a smooth, creamy PVA. Under UV the fluorescence level is generally very brght on the front, being at least MF or HF. On the back there is a wide range of fluorescent reactions from LF through to HB. On their own, most stamps look HB on the back, but it becomes apparent when you compare one stamp to another that there are some stark differences. Occasionally this paper will contain varying concentrations of fluorescent fibres.
- Fluorescent Coated Paper (FCP) - This paper is whiter than the OCP and glows very brightly under UV light on both the front and the back. By and large most stamps are HF or HB on both the front and the back. The gum is sometimes the original cream gum, but is most commonly the bluish green PVAD gum (PVA with added dextrin). FCP was introduced in 1974-1975. This paper never contains any fluorescent fibres, the fluorescence being uniform and clear.
- Advance Coated Paper (ACP) - This paper is similar to FCP, but is even brighter under UV. The gum is less bluish than the earlier PVAD, but is not the cream colour of the OCP.