Unitrade 's listings for this stamp are fairly straightforward for the untagged stamps. There are just four listings included to cover all of the untagged printings made from 1967 to 1973. These are quite inadequate to describe all of the variations that can be found, as we shall soon see. The tagged stamps are accorded many more listings in Unitrade, with seven variations listed. However, again, this is an over-simplification of what actually exists.
This is one of the few values of the set that was issued in booklets, and also one of only two that are known to exist on paper that shows clear horizontal ribbing on the surface, the other value being the last printings of the 6c black. This ribbed paper is found quite extensively in the next definitive issue that replaced this one in late 1973. So it would seem logical to conclude that stamps on this paper are from extremely late printings made in very late 1973. The only booklet to contain this stamp is known to collectors as the OPAL booklet, because it was produced by the OPAL Manufacturing Co., based in Toronto.
Today's post will examine the OPAL booklet stamp and the untagged stamps that were issued both with dextrose gum and PVA gum.
The untagged stamps can thus be divided into three broad categories:
- The stamps issued with dextrose gum, and printed from plates 1 and 2 between February 1967 and March 1972.
- The stamps issued with PVA gum, printed from plates 1 and 2 also, from March 1973 until October 1973.
- The OPAL booklet stamps with dextrose gum.
The block on the left is a dull fluorescent yellowish grey, while the one on the right is a low fluorescent bluish grey with very few medium fluorescent fibres visible in the paper.
The block is an dull fluorescent greyish colour under UV, while the middle stamp is dull fluorescent greyish white, and the far right stamp is dull fluorescent grey.
These are both dull fluorescent ivory, but the block on the right contains a few low and medium fluorescent fibres.
The left stamp is a non fluorescent deep bluish grey, while the block is a non-fluorescent grey colour.
The block on the right is printed in deep dull green, while the one on the left is myrtle green, according to the Gibbons colour key.
The block on the left is paler myrtle green, while the one on the right is green on the Gibbons colour key.
The block on the left is deep green, while the one on the right one is deep bright green.
- A stiff vertical wove paper that appears slightly off-white against a bleached white background, but is very white compared to the cream papers that were used for the dextrose gum printings. When you look at this paper under magnification, it has a very smooth surface, and you can see fibres on the surface, but they are not loose. Quite often, if you view the paper against strong back-lighting you can just make out fine vertical striations in the paper. These are sometimes visible on the gum as well.
- A stiff vertical wove paper that also appears slightly off-white, though a shade whiter than the smooth paper does. Under magnification, the ribbed surface is what is most noticeable, but again, if you look closely, you can see what appears to be a very light surface coating that keeps the fibres of the paper that are visible on the surface from coming loose.
The block on the left appears much more deep grey in reality than it does in the above picture. It is a dull fluorescent deep grey, which almost borders on being non-fluorescent. But it contains a sparse concentration of low, medium and high fluorescent fibres, which make it appear LF overall. The right block is on dull fluorescent greyish paper that contains a sparse concentration of low and medium fluorescent fibres, and a very sparse concentration of high fluorescent fibres. The single stamp is printed on a dull fluorescent greyish white paper with very sparse concentrations of low, medium and high fluorescent fibres visible in the paper.
- 3 basic paper types.
- 9 varieties of fluorescence (5 for smooth paper and 4 for ribbed).
- 4 shades for smooth paper and 3 for ribbed.
- one perf.
- two plates.
- two gum types that are specific to smooth and ribbed papers.