Today's post will be the first of two posts that will explore the tagging that is found on many stamps of this issue. Collectors with even a passing familiarity with this issue will know that there were two basic types of tagging used on this issue: Winnipeg tagging and Ottawa tagging. Today's post will look at the first of these in depth: Winnipeg tagging. The Winnipeg tagging was first introduced in 1962, and so was in use on all printings of the low values from 1967 until 1972 when Ottawa tagging began to replace it. Interestingly, the tagging was not introduced on the high values until December 9, 1969.
Tagging is of course, a chemical overprint that was applied to the surface of the stamps after printing. Like any overprint, there are several attributes which can show variation, and are worthy of study:
Tagging is of course, a chemical overprint that was applied to the surface of the stamps after printing. Like any overprint, there are several attributes which can show variation, and are worthy of study:
- The chemical makeup of the taggant compound used, as evidenced by its reaction under UV light.
- How much taggant was applied, as evidenced by how visible the tagging is to the naked eye, when the affected stamps are examined carefully.
- What the configuration of the tagging was on the stamps, i.e. how was it applied?
- What are the characteristics of the setting used, i.e. how wide are the tag bars and how far apart are they?
Many collectors know that there were two basic configurations of Winnipeg tagging on this issue: 2 bar tagging, and single centre bar tagging. To most collectors, this is where it ends. However, as we shall see, all of the above attributes show consistent variation that warrants inclusion in a specialized collection, and in addition, the characteristics of the tagging differs, depending on whether the stamps were printed by the CBN or the BABN.
The remainder of these posts will explore these differences.
Chemical Makeup of the Taggant Compound: Colour Under UV Light
In examining several tagged stamps, it becomes apparent that the tagging bars glow slightly different colours under long-wave ultraviolet light. The colours differ between the CBN and BABN printings, as does the intensity and duration of the afterglow, when the UV lamp is switched off. The existence of an afterglow is a phenomenon that is unique to Winnipeg tagging. With Ottawa tagging, you get a very bright glow as long as you view it under UV light, but that glow disappears completely when the lamp is switched off. However, with many types of Winnipeg tagging, the glow will persist, will often appear more visible when the lamp is switched off, and will immediately begin to fade, until there is no glow anymore. The length of time that the afterglow takes to fade out completely varies from nearly instantaneous, to a few seconds. The differences in colour, as well as the length of the afterglow, are both indicative of differences in the chemical makeup of the tagging compound that was employed.
CBN Printings
On the low value stamps printed by CBN, I have found four different colours of tagging:
- Pale bright yellow
- Bluish white
- Pale green
- Brownish yellow
From what I have seen, the bluish white tagging is the least common of the four, while the pale green is the most common. In terms of visibility to the naked eye, the darkest tagging, that which appears deep yellow to the naked eye, tends to look pale bright yellow under UV, or pale green. The bluish white tagging is usually so pale to the naked eye, that the stamps with it often appear to be untagged. The pale green tagging usually appears light yellow to the naked eye, so is neither dark, nor light. In all cases, you can see the tagging bars if you hold the stamp at an angle to the light and look along the surface. Even the lightest tagging can be seen fairly easily in this manner without the aid of a UV lamp.
Here is a picture of the first three types as seen under UV light:
The yellow tagging is shown on the left, the bluish white is in the middle, and the pale green is on the right. The differences are a little more difficult to see in the picture than they appear in reality. However, you can see the difference quite clearly on the stamps with centre bar tagging: there is a clear yellowish tone to the two 1c stamps, while the band on the 2c stamp is clearly greenish. The colouring of the tagging seems to be the same whether the stamps have dex gum or PVA gum, as the two 1c stamps shown on the left have both types of gum, but have tagging that appears more or less the same - both in regular light, and under UV. To see the afterglow on these types of tagging, it is essential to shine your UV light directly on the stamps, in a completely dark room. Then after at least 30 seconds of exposure, switch off the lamp. You should see an afterglow then that lasts for between 2 and 3 seconds.
The brownish yellow tagging only seems to occur on the stamps printed on hibrite paper. Basically, the colour of the tagging appears more or less the same under UV as it does in normal light. Here is an example of the 1c on hibrite paper with the centre bar tag:
The tagging bar is very difficult to see, but if you look just to the left of centre in the margins, you will notice a very slight darkening of the paper, and if you focus on this, you will start to see the light vertical band. This lack of visibility on hibrite paper though is one of the reasons why I believe Winnipeg tagging was discontinued. I think that the cancelling machines were simply not able to see the tagged stamps when either the stamps or the envelopes were made with hibrite paper. There is also no afterglow whatsoever with this tagging.
On the CBN High Values, I have found pale yellow and an extremely pale yellow that is nearly invisible. This later colour is only found on the hibrite paper with the Spotty PVA gum, and may appear to be nearly invisible under UV only because it is being overshadowed by the very intense glow of the hibrite paper. In normal light, however, it is usually very light also, and easy to miss.
Here is a scan showing some of the high values with the Winnipeg tagging:
The first two 15c stamps on the top row have PVA gum, one being eggshell, and the other a matte PVA. The third 15c on the top row has dex gum. In all three cases, the tagging bars are clearly visible and are a pale yellow colour. The tagging on the 10c stamp is very similar in appearance to the tagging on the 1c hibrite stamp that was just shown, and can only just be seen as a very, very slight darkening of the sides of the stamp. The tagging on the 25c hibrite stamp is similar again, but shows more pronounced darkening. In reality, it is probably the same pale yellow that the 15c stamps are. It's just that the appearance has been so completely altered by the brightness of the paper that the stamp is printed on. The afterglow for the high values was about a second longer than on the low values: 3-4 seconds for the stamps on non-hibrite paper, and 1 second or so for the hibrite paper stamps.
BABN Printings
On the BABN stamps, being the 6c, 7c and 8c low values, the tagging is much more difficult to see,both in normal light, and under UV. In fact, some of the tagged stamps look untagged under UV, when they are clearly tagged in normal light. In terms of colour, the tagging varies from very pale yellow, to yellowish white, to greyish white, to colourless. In normal light, only the pale yellow and yellowish white tagging are clearly visible. The others appear very light, and take some experience to see. Unlike the CBN stamps, you will not be able to see the tagging bars by holding the stamp up at an angle to the light, or at least, I have never been able to see the bars this way.
Here is a picture showing some of the different types of tagging on three of the BABN low value stamps:
If you look closely you can clearly see the yellowish white tagging on the centre block and lower left blocks, as well as the 6c with centre band. The 8c library stamp at the right is clearly the very pale yellow. In contrast, the tagging of the 6c black block, and the upper right 6c orange block is barely visible, and is either greyish white, or is colourless. The afterglow on these is the longest of all the Centennial stamps, with the yellow tagging glowing for approximately 3 seconds, while the other colours glowed for 4-5 seconds. The colour of the afterglow itself was generally bluish white, compared to pale yellow for most of the CBN stamps.
Intensity of the Taggant Applied: Visibility of the Tag Bars
In addition to the colour of the tagging under UV, there is also the intensity of the tagging, which is dictated by the amount of taggant applied, or the type of chemical used. The intensity is expressed in terms of how visible the tagging is to the naked eye. I distinguish between three levels of intensity:
- Heavy - in which the bands are dark yellow and obvious.
- Moderate - in which the bands are light yellow. They are clearly visible to the naked eye, but are not dark.
- Light - in which the bands are barely visible to the naked eye.
Some visual examples will be shown under each of the main printers below.
CBN Printings
Heavy tagging - note the dark yellow bands.
Moderate tagging - you can see the bands clearly, but they are not dark.
Light tagging - here you have to look hard to see the bands.
The tagging of the CBN printings runs the entire gamut from dark to light, though I would note that the 4 mm centre bar tags are almost always dark, or possibly moderate. I have never come across any light centre bar tags. The 2 bar tagging is found in all three strengths, and as far as I can tell, for all values in the set that exist tagged.
BABN Printings
All the BABN stamps that I have examined have either light, or moderate tagging. I have never seen a BABN stamp with dark tagging. Here are some visual examples of how the tagging looks on these stamps in normal light:
Moderate tagging - the bars are clearly visible, though on the 6c black they are tending towards being light.
The 8c stamp has light tagging where you can barely see the bars. The 6c actually has moderate tagging in which you can see a pale yellow band down the centre. This picture makes it appear lighter than it actually looks.
Configuration of Tagging on Affected Stamps
CBN Printings
On the CBN printings, vertical tagging bars were applied across the panes in the horizontal direction, and these bars were either applied across the stamps, forming a single vertical tag bar, or they were applied down the perforations of the stamps, so that each stamp would wind up with 2 partial bars, one on each side.
Occasionally, the tagging was misapplied in the horizontal direction, which in extreme cases, resulted in an extra wide, single tagging bar on the 2 bar tags. These can be found, shifted over to either the left, the right, or the centre of the stamp. They are quite scarce and sought after. Here is an example of such a shift on the 2c green:
The pair at the top shows the tagging error, with the extra wide tagging bar at the right. It results from an approximately 5 mm shift of the bars to the left of where they should be.
Interestingly, I have never seen a similar shift in the 4 mm, 1 bar tagging. Extreme shifts, if any exist, should result in the creation of 2 bar tagging that has extremely narrow bars of just 2 mm or so on each side of the stamp. I suspect that such shifts may exist, but may be mistaken for general Ottawa tagging, and simply not checked. There are no listed varieties in the general tagging of most values in this series, and since the general Ottawa tagging is so readily identifiable without the aid of a UV lamp, most of it never gets checked under UV. This might be why no tagging errors of this kind involving the 1 bar 4 mm tagging have been reported so far.
Although the bars were applied continuously in the horizontal direction across the panes, they were not applied continuously in the vertical direction. Instead, there were two sets of bars, that are separated by a small gap. You can see this on corner blocks that come from the bottom of the upper panes, or the top of the bottom panes. The following picture shows an example of this vertical gap between the tagging bars of the 2c green:
This lower right block shows the top of the vertical tag bars for the pane that would have been located below the one that this block is from. Given that the panes were arranged in a 3 x 2 format, this would appear to be from the upper right pane, since there is no partial tag bar at the right of the selvage tab, which there would be if this was from one of the centre panes.
BABN Printings
Like the CBN printings, the BABN printings had the tagging bars printed continuously over the panes in the horizontal direction. However, they also appear to have been printed continually in the vertical direction as well, as I have yet to see a block that shows the kind of partial bars in the selvage that we see with the CBN printings like the 2c above. In contrast, the tagging bars on the BABN printings go right to the edge of the selvage on all the 6c, 8c and 8c blocks that I examined.
The tagging errors involving shifting of the bars that are found on the CBN printings with 2-bar tagging, are also known on the BABN printings as well. I have seen them most often on the 8c, but my understanding is that they exist on all four of the values printed by BABN.
Width of the Tagging Bars
CBN Printings
On the CBN printings with 2-bar tagging, the tagging bars are approximately 8-8.5 mm wide and were placed down the vertical columns of perforations so that each stamp would have 2 bars that were approximately 4-4.25 mm wide. On the stamps with centre bar tagging, the bars are 4 mm wide.
BABN Printings
On the BABN printings, the tagging bars of the 2 bar stamps are of different width, depending on whether the bar is located at the left edge of the sheet, or whether they are from any of the other columns. On the 6c, the regular bars seem to be approximately 7-7.5 mm wide, which is a full 1 mm narrower than the bars on the CBN printings. On the left side of sheets, the bars between the selvage and the first column of stamps are only 5.5 mm wide. The centre bar tag on the 6c die 2 stamp is 4 mm - the same wide as the centre bar tags on the CBN printings. On the 7c and 8c stamps, the bars are 8 mm wide all across the sheets.
Spacing Between Tagging Bars
CBN Printings
On the CBN printings the spacing between the tag bars is usually about 16-16.5 mm on the low values with 2-bar tagging, and approximately 21 mm for the 1-bar tagging. However, there is difference in the spacing between the first two vertical columns of tag bars on the left side of the sheet. Generally on the left hand side of a sheet, the spacing between the first two tag bars is approximately 1 mm less than for all the other columns. This will generally be apparent when comparing the spacing of the tag bars on upper left and lower left corner blocks as compared to upper right and lower right blocks. Here is a picture showing this difference in spacing clearly:
The block on the top is a lower right block, while the block at the bottom is an upper left block from one of the centre panes. The low value centennial stamps were printed in sheets of 600 that were arranged in six panes of 100, arranged 3 panes by 2 panes. We can tell that this bottom block is from a centre pane by the fact that the selvage on both sides is extremely narrow and the sliver of a tagging bar that is visible in the selvage at left. The tagging bars were applied continuously across all three panes in the horizontal direction, and so the presence of two partial tagging bars in the selvage tab indicates quite clearly that this block cannot be from one of the outer panes. In this picture, you can clearly see the difference in the spacing between the tag bars on the top block, and on the lower block.
On the high values, the spacing is 27-27.5 mm and 28-28.5 mm, with the same 1 mm difference occurring on the left side of the sheet. Here is a picture showing the difference in spacing:
The stamp on the top has the narrower spacing, and has a selvage tab on the left side, which shows that it comes from the left side of the pane. The panes, as far as I understand were arranged 2 x 3, so that stamps with very narrow selvage on the left side will have come from one of the three right hand panes. This stamp has narrow selvage on the left, so I believe that it is from one of the right hand panes.
BABN Printings
The spacing between the tagging bars on the BABN stamps is much more difficult to measure, due to how difficult the bars are to see in normal light. However, it would appear that for the 2 bar tagging, the spacing is wider - 18 mm on the first two columns of the left side of sheets, and 16 mm between all other columns. I do not have any multiples of the centre bar tagging on the 6c black to check the spacing, but I assume that it is 21 mm, just like the centre bar tagging on the CBN printings. I will confirm this once I have an opportunity to examine a block.
This concludes my discussion of the Winnipeg tagging on this issue. Next week, I will look at the Ottawa tagging that was introduced toward the end of 1971 to replace the Winnipeg tagging.