Search This Blog

Tuesday, October 31, 2017

Ottawa Tagging on The 1967-1973 Centennial Issue

Today's post is the second post that will deal with the tagging used on the 1967-1973 Centennial Issue. Last week, I looked at the Winnipeg Tagging, which began to be replaced in late 1971 and was fully superseded in 1972, by what is known to collectors as General Tagging, or Ottawa Tagging. This is now the standard tagging that is found on nearly all Canadian stamps since that time. However, the process of replacing the Winnipeg tagging with the new Ottawa tagging, was not without its experimentation as well, and it is this experimentation that has led to the existence of additional collectible varieties that go beyond the mere Ottawa Tagging itself.

The points of interest, where varieties occur, that will be discussed in today's post are:


  • Variation in the chemical composition of the taggant compound: OP-2 versus OP-4 tagging.
  • Variation in the colour of the tagging under UV light.
  • Intensity of tagging bars in normal light.
  • The width of the tagging bars.
  • Tagging errors.
  • Spacing of the tagging bars and configuration on the sheets. 
None of the Ottawa tagging exhibits any afterglow. The glow under UV is very bright while the UV light source is shone directly on it, but when the lamp is switched off, any visible glow abruptly disappears. 

OP-2 Versus OP-4 Tagging

Initially when Ottawa tagging was first introduced, the taggant compound used had the trade name OP-4. This taggant compound was found to be unstable, and migrated from the stamps onto other stamps and any substrate with which they came into contact. Because of this, a new compound was introduced almost immediately, with the name OP-2. This later compound was chemically stable and has been in use ever since. 

OP-4 Tagging


The above picture shows two 25c booklets, each with the two different types of tagging. The OP-4 type is shown on the right. Generally, the OP-4 is recognizable by the colour, which although it does vary, it always has a pale, faded appearance, due to the migration that has taken place over the years. In contrast, the OP-2 tagging always appears deeper and brighter, as shown by the booklet on the left. 

The migration of the tagging can best be seen by examining the back of affected stamps under a UV lamp. Depending on how severe the migration is, the back will have an uneven fluorescence, with an apparent diffusion of the tagging throughout the back. I don't have an example of this on this issue that shows up well in a picture. However, I do have several blocks and pairs from the next issue, the 1972-77 Caricature issue, that show the appearance of this migration very well:



The block on the left is only very mildly affected, and the migration is really only apparent within about 3 mm on ether side of each row of perforations. In contrast, the migration is so severe in the right pair, that the fluorescence of the paper has been completely distorted by the taggant compound. 

The Unitrade catalogue asserts that such stamps are damaged. I do not agree entirely with this assessment, as the vast majority of OP-4 tagged stamps are affected in this way to a more or lesser extent. I think that from the perspective of collecting and studying the paper varieties, that yes, such examples are not desirable because the reading of the fluorescence is not a "true" reading. However, for collectors who are simply seeking a collectible, basic example of the OP-4 stamps, I think that provided they are sound in all other respects, they are perfectly good stamps. 

The OP-4 tagging only seems to be found on some of the booklet stamps that were printed by the BABN, being the 1c, 6c, and 8c. None of the CBN stamps have been found thus, nor have the other stamps printed by the BABN been found with this type of tagging. 


OP-2 Tagging


The booklet pane shown on the left is the OP-2 tagging, which is easiest to spot by the depth of the colour. OP-2 tagging appears both bright and solid, and not washed out. 


Colour of Tag Bars Under UV Light

The colour of the tagging bars for both OP-2 and OP-4 tagging exhibits some variation under the UV light. The colour varies from pale greenish yellow, to pale green, to deep yellow, to an orangy yellow. 

OP-4 Tagging

All of the OP-4 tagging that I have seen on this issue appears either pale green or pale greenish yellow, as shown in the pictures below:


This picture shows a 1c booklet stamp with 4 mm OP-4 tagging on the top row, and a pair from a booklet, with 3 mm OP-2 tagging on the bottom row. In this example, the OP-4 tagging appears pale green. 



Here is a block of 4 of the 1c, this time from the $1 booklet that was issued in 1972. In this instance, the tagging appears slightly more yellowish, being a bright greenish yellow. 



Here is an example of a 1c booklet stamp with 3 mm OP-4 tagging that appears a pale yellow. 

OP-2 Tagging

OP-2 tagging in contrast to the OP-4 tagging appears either a bright yellow, a very bright greenish yellow, or a bright orangy yellow on this issue. It tends not to appear green, but more yellowish. 


In this picture, the bottom 1c pair which comes from one of the 25c BABN booklets is tagged with 3 mm OP-2 tagging. The tagging glows a bright yellow under the UV light. 



In this example, the booklet on the left has the OP-2 tagging, which is 3 mm wide, and glows a light, bright greenish yellow. 


Here, we have a block of the 6c black CBN sheet stamp, with 4 mm OP-2 tagging, that glows a very bright greenish yellow. Although there is a clear greenish tone to the yellow, there is much more yellow than green to the colour. This is the colour of most Ottawa tagging that is found on most stamp issues, even today. 



Finally, here is an example of one of the CBN high values, with the 4 mm OP-2 tagging. In this case, there is less green in the yellow, to the point that this is more a pale, bright yellow. 

Intensity of Tag Bars Under Normal Light

Like the Winnipeg tagging, the appearance of the tagging on the stamps varies in normal light, from light tagging, that is barely visible to the naked eye, to dark yellow bars that are impossible to miss. 

Light Tagging


Here is a block of the 1c reddish brown with PVA gum, that is tagged with 4 mm OP-2 tagging. As you can see, the bars are just barely visible, and could easily be overlooked if you weren't looking for them. 


Moderate Tagging



The above picture shows a 2c green on ribbed paper, with PVA gum that is tagged with 3 mm OP-2 tagging, that is moderate in its intensity. The bars appear a light yellow in normal light, and although they are clearly visible, are by no means dark. 

Dark Tagging


Here we have a corner block of the 4c bright carmine with PVA gum and 3.25 mm OP-2 tagging. In this case, the tagging bars appear a dark yellow, and it is impossible not to notice them. 



Here is an example of the 10c Jack Pine with PVA gum that has dark 4 mm OP-2 tagging. 

Width of Tagging Bars

OP-4 Tagging

The OP-4 tagging is found in two different widths: 3 mm and 4 mm. Both appear to have been in use concurrently, as they first appear on the 25c booklets, which were printed by BABN, and first issued on December 30, 1971. 


The booklet pane on the left is tagged with 4 mm OP-4 tagging. 


The above 1c booklet stamp is tagged with 3 mm OP-4 tagging.

Telling The Widths Apart

Measuring the width of the tagging is easy on multiples where you have a full tagging bar. But on single stamps, it becomes more difficult. One way to identify the type positively is to measure the space between the bands. 4 mm tagging will have a gap of 20 mm between the bars, whereas the 3 mm tagging will have a 21 mm gap. This is a sure-fire test. However, it is also time consuming because of how long it takes to measure the space between tag bars. A good, quick visual test is to look at the degree to which the bars occupy the margins and overlap into the stamp design. With a 4 mm band, you will generally see a considerable amount of overlap into the design on one of the two sides. With the 3 mm tagging, you will usually see the tagging take up the margins on both sides, but not overlap into the design that much. If, you do see overlap on one side, it will be offset by almost no tagging being visible on the opposing side. Look at the above pictures again, and you will see what I mean. 

OP-2 Tagging

It was taken for granted for the longest time, that all the OP-2 stamps had 4 mm tagging. However, that is not the case. In addition to 4 mm OP-2 tagging, I have seen 3 mm OP-2 on some of the booklet stamps, as well as 3.25 mm OP-2 tagging on some of the CBN sheet stamps. 


Here is an example of the 1c with 4 mm OP-2 tagging. I have found that the 1c, 3c precancel, and some printings of the 6c black CBN stamps have 4 mm tagging. 



Here is an example of the 15c Bylot Island with 4 mm OP-2 tagging. All of the high values printed by CBN, that exist with Ottawa tagging, being the 10c, 15c, and 20c are generally found with 4 mm tagging. 



In this picture, the 1c pair from a booklet on the right, is tagged with 3 mm OP-2 tagging. The 3 mm tagging is found on some printings of the BABN booklet stamps, the later printings of the 8c slate library that are found with OP-2 tagging, and some printings of the 6c black CBN sheet stamp. 



Finally, the 4c bright carmine, shown above, has what at first appears to be 3 mm tagging. I measured the tagging on this block and found that it is in fact not 3 mm exactly, but 3.25 mm. I have seen this tagging on some printings of the 4c, and the 2c. 

Tagging Errors

As was the case with the Winnipeg tagging, all the known forms of Ottawa tagging exist with severe horizontal shifts, resulting in apparent one bar tagging errors. Unfortunately, I do not currently have an example of such an error to show. However, I do have an example of a 1c with 4 mm Op-2 tagging, that is shifted so far to the left, that the left tag bar is almost completely missing, touching just the perforations at the edge:



Spacing Between Tagging Bars

The spacing between the tagging bars varies, depending on whether the stamp was printed by the BABN or CBN, whether it is a low value or a high value, and what the width of the tagging bars are. The spacings that I have found in my examination of the stamps of this issue are as follows:

  • 3 mm OP-2 and OP-4 - BABN  stamps and 6c black CBN sheet stamp:  21 mm
  • 4 mm OP-4 booklet stamps and 6c black CBN sheet stamp with 4 mm OP-2: 20 mm
  • 3.25 mm OP-2 CBN sheet stamps: 22.5 mm
  • 4 mm OP-2 high value CBN stamps:  28 mm

Configuration of  Tagging Bars on the Sheet

In the case of Winnipeg tagging, the bars were seen to be printed continuously across the sheets in a horizontal direction, but not continuously in the vertical direction, requiring more than one application to tag all 600 stamps in the full sheets. However, it appears that the Ottawa tagging was applied continuously in both the horizontal and vertical directions:

  • The spacing between the tagging bars is the same, no matter which position on the sheets we are looking at, and no matter which pane is being examined. 
  • The tagging bars generally extend the full length of the selvage in a block, except for blocks located in the bottom panes. On those blocks, the tagging stops just short of the bottom of the selvage. However, there is no evidence of any "next series of bands" that we often see on the Winnipeg tagged blocks from the centre panes. Generally, any block coming from one of the centre panes will show tagging that extends the entire length of the selvage.



Here is an example of a lower left block that comes from one of the bottom panes. Because the width of the selvage is the same on both sides, it is reasonable to conclude that this block comes from the lower left pane, as there would be no need for the tagging bars to extend all the way to the bottom. 


In contrast, this block of the 4c bright carmine shows tagging that extends all the way through the selvage at the top. This suggests that the block comes from one of  the lower panes. In this case, the selvage tab at the left is wider than the one on top. That suggests that the left edge is one of the outer sheets, but the top edge is shared with an adjacent sheet. Thus the only logical position for this block is the upper left position of the lower left pane. 

This concludes my discussion of the Ottawa tagging on this issue. Next week's post will be a shorter one discussing the perforations found on the issue, and then in the two weeks following next week, I will look at the plate characteristics, starting with the die type differences on the 6c, and the plate flaws found on the other values. 

Tuesday, October 24, 2017

Winnipeg Tagging on the 1967-1973 Centennial Issue

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:


  • 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. 


Tuesday, October 17, 2017

Printing Inks Used On The 1967-1973 Centennial Issue - Part Eight of Eight

Today's post will complete my discussion of the inks used on this issue as they appear under long-wave ultraviolet light. Last week's post examined up to the 15c Bylot Island. This week, I will look at the 20c through $1 values.

20c Dark Blue - The Quebec Ferry

The inks used to print this stamp are primarily non-transformative in that in most cases, the appearance of the colour under UV light is either the same as, or just a bit darker than how the colour appears under normal light. There are however, some cases in which the ink loses much of the blue and becomes either a very deep blue-black, or black under the UV light. These inks are transformative.

Non-Transformative Ink

Let's take a look at three stamps printed with non-transformative ink:


On the left we have a deep bright blue, printed on horizontal wove, low speckled fluorescent paper with type 4 dex gum. In the centre is a deep violet blue on horizontal wove, dull fluorescent paper with type 1 dex gum, and on the right, we have a bright blue Winnipeg tagged stamp on low fluorescent, horizontal wove paper with satin PVA gum. 

Let's take a look at them under UV light:


In this picture, all three of the stamps look very similar, but in reality, the stamp in the centre is the darkest. In all three cases, the inks appear darker than they do in normal light, but all three of them are shades of blue, which are not substantially different from the shades under normal light. This is why I have classified them as non-transformative. 

All of the PVA gum stamps I have examined so far, appear to have been printed with non-transformative ink. 

Transformative inks

I have only come across two examples of this stamp in the transformative ink:


On the left is a deep blue stamp printed on dull fluorescent, vertical wove paper, with type 4 dex gum, and on the right, a deep blue stamp on horizontal wove hibrite paper with type 4 dex gum also. Both stamps in normal light are a very clear, deep blue.

Here are the same two stamps under UV light:


This picture is another excellent illustration of the vast difference in appearance, between dull fluorescent paper and hibrite paper. The stamp on the left is still a little bluish, but the colour has acquired so much black that I consider it a transformative ink. The appearance of this stamp under UV is very similar to the appearance of the middle stamp in the first group above. The difference though, is that the middle stamp from the first group already looks blue black in normal light, whereas the stamp shown here looks much brighter blue. The ink of the stamp on the right, as expected, appears black, as do most stamps on hibrite paper.


25c Myrtle Green/Slate Green - The Solemn Land

From the stamps I have examined, the vast majority are printed in transformative ink which tends towards blackish green or black under UV light. A few printings were made in dull blue green which appears either darker under UV, or the same as normal light.

Non-Transformative Ink

Let's take a look at two stamps which are printed in non-transformative ink:


Both of these stamps are printed with dark grey-green ink that contains a hint of blue, with the stamp on the right, being slightly darker than the one on the left. Both are printed on horizontal wove, dull fluorescent paper. The stamp on the left has type 4 dex gum, while the stamp on the right has type 3 dex gum.

Here are both stamps under UV light:


Both stamps appear blackish in this picture, but in reality, enough of the green remains in the colour that I consider this ink to be non-transformative.

Transformative Ink

Let's now look at five stamps that are printed in transformative ink:


On the first row we have three deep grey green stamps, all printed on dull fluorescent paper. The paper of the left stamp is horizontal wove, whereas the centre and right stamps are on vertical wove paper. The left and centre stamps have type 4 dex gum, while the right stamp has type 1 dex gum, and is Winnipeg tagged. On the second row is a dark bluish green stamp, on vertical hibrite wove paper, Winnipeg tagged and with type 4 dex gum. 

All of these five stamps contain a significant amount of green under normal light, although in the case of the top three stamps it is a very dark green containing some black. 

Here are the same five stamps under UV light:


On the top three stamps, the ink almost appears black. There is still a very slight hint of green, but it has acquired so much black compared to how it appears in normal light, that I consider these inks to be transformative.

As is the case with practically all the hibrite stamps examined so far, the bottom stamp appears to have been printed from black ink.


50c Orange Brown - Summer's Stores

In terms of inks, this is one of the more interesting values in the series, because of the dramatic difference that introducing UV light makes to the appearance of most of the stamps. In ordinary light, the colour of this stamp is either a shade of brown orange (most commonly), or it is a shade or orange brown (less common). With only a few exceptions, the ink completely changes colour under UV - usually to shades of dark brown, dark red-brown or black.

Non-Transformative Ink

All of the PVA gum stamps that I have examined thus far, and a few of the dex gum printings made on dull fluorescent paper, are printed in non-transformative ink. The colour appears far, far darker than in normal light. However, enough of the orange remains visible, that the fundamental colour under UV is not any different than under ordinary light.

Here are two such stamps in ordinary light:


Here we have a light brown orange printed on dull fluorescent vertical wove paper with type 4 dex gum and a deeper brown orange on low fluorescent horizontal wove, with satin PVA gum. 

Here they are under UV:


In this picture, both inks appear quite blackish. In reality, while they are dark, both are very clearly shades of brown orange, and hence the reason why I classify these inks as non-transformative.

Transformative Inks

Now, lets take a look at 6 stamps printed in transformative ink:



The first two stamps on the top row are both printed on low fluorescent paper, and are both the brown orange shade. Both are printed on horizontal wove paper, and the gum on the left stamp is type 4 dex, while the one in the middle is type 1 dex. The stamp on the right is a orange brown shade, and is printed on non-fluorescent vertical wove paper, with type 4 dex gum. Moving on to the second row, on the left we have a golden brown shade printed on horizontal wove, non-fluorescent paper with type 4 dex gum as well. The centre stamp is an orange brown shade on dull fluorescent, horizontal wove paper with type 4 dex gum. Finally, the stamp at lower right is a brown orange shade on hibrite vertical wove paper, with type 4 dex gum. 

Now, lets take a look at them under UV:


This picture shows the differences between low fluorescent, dull fluorescent and non-fluorescent papers quite nicely. As you can see, all of the colours look dramatically different under the light. The upper right stamp is the closest to the brown orange colour, but it has become so deep that it looks more deep brown than orange, even though some orange is still coming through. The middle, top right and bottom left stamps are a very deep red brown. The middle stamp is a deep, orangy brown, which is much closer to brown than it is to orange. Finally the lower right stamp, as with most all the hibrites appears black. 

$1 Carmine Red - Edmonton Oilfield

Except for the printing on hibrite paper, all of the $1 stamps that I have examined are printed in non-transformative ink. The basic colour is deep scarlet red with a hint of carmine, and for most stamps, this colour merely appears deeper under the UV light. But in all cases, it is clear that the colour is a deep scarlet red or carmine red.

Non-Transformative Inks

Let's start with five stamps printed in non-transformative ink.


On the top row are three dex gum printings, all in the deeper, carmine-red shades. Then on the bottom row are two PVA gum printings, each in the same scarlet-red shade. The left and right dex gum stamps are both on dull fluorescent, vertical wove paper, with type 4 dex gum. The centre dex gum stamp is on low fluorescent, horizontal wove paper with type 4 dex gum. Both bottom stamps are printed on low fluorescent vertical wove paper, with satin PVA gum. 

Here are those same stamps under UV light:



Unfortunately, this picture obscures the differences between these stamps and makes them all appear blackish under the light. In reality the top two stamps both appear more or less the same carmine-red colour that they appear in normal light. The stamp at the top right appears much darker, but still a clear carmine-red. On the bottom row, both stamps appear carmine red, but the left stamp is a brighter colour than the right stamp. I have also examined a copy of the PVA gum printing on medium fluorescent paper and can confirm that it displays the same ink characteristics as the printings on low fluorescent paper. So I have not felt the need to illustrate it here.

Transformative Ink


Here is an example of the bright scarlet-red on hibrite vertical wove paper, with type 4 dex gum. As expected, when examined under UV, the ink colour appears black:



This concludes my examination of the inks used to print the Centennial issue stamps. Next week's post will start to examine the Winnipeg tagging that was added to some printings of the stamps made between 1967 and 1972. Unitrade only lists the basic tagging configurations, but there were variations in the intensity of the taggant coating and in the appearance of the tagging under UV, as well as the width and spacing of the tag bars themselves.