The 1c Brown Northern Lights and Dogsled Stamp of the 1967-1973 Centennial Issue - Part One

Today, we delve into the individual stamps of the fascinating 1967-1973 Centennial issue. We start with one of the most complex of the stamps from this issue: the 1c Northern Lights and Dogsled design. Perhaps the only stamp more complicated than this is the 8c slate Parliamentary Library.

Because of this complexity, I have decided to deal with this stamp over four separate posts, which will be as follows:

1. The sheet stamps with Dextrose gum, both tagged and untagged.
2. The sheet stamps with PVA gum, both tagged and untagged.
3. The CBN booklet stamps, perf. 12 and the BABN booklet stamps perf. 10.
4. The perf. 12.5 x 12 booklet stamps that come from the 25c, 50c and $1 integral booklets.

Once I have presented these stamps in detail, I will conclude with a sorting algorithm which will help you sort through large quantities of mint and used stamps, with maximum efficiency, as there is an optimal sequence of steps to follow. Of course, there is more than one way to approach sorting thesse stamps, but only one way that is most efficient. 

In terms of Unitrade listings, there are four basic listings for the untagged stamps:

1. Dull fluorescent paper with separate plate block listings for plates 1-2, 3 and 4.
2. Non-fluorescent flecked paper.
3. Hibrite paper.
4. Precancelled on dull fluorescent paper.

There are three listings for the tagged stamps:

1. Dull fluorescent paper, with 2 bar Winnipeg tagging.
2. Dull fluorescent paper, with Winnipeg centre bar tagging.
3. Hibrite paper with Winnipeg centre bar tagging.

In reality, things are quite a bit more complicated than this. For starters, there are several different varieties of dull fluorescent paper that appear different colours under ultraviolet light. These colours range from ivory to light violet. In addition, the non-fluorescent paper also appears in several different colours as well. Then the gum varies, with all the different types as discussed in my earlier posts dealing with the dextrose gum. The papers can all exist with different concentrations of fluorescent fibres. Next, the tagging can vary, both in terms of spacing between the tagging bars, the existence of tagging errors, in which the 1-bar tags exist with wide bars, which are actually 2-bar tags that have been shifted so severely as to produce 1-bar tags, the intensity of the bars in normal light, and the colour under UV light. Finally, the shades of the brown ink vary, from a deep, dull violet brown, to a bright brown. 

I will take each of these attributes in turn and go through each of these listings, and expand them to include as many varieties as I cab identify. Please note, that I am limited by the stamps that I actually have in stock to work with, so that this, and all the remaining posts of this issue mus be considered a work in progress. 

Finally, on most if not all of the varieties listed here, the stamps will exist with up to four different line perforations: 11.85, 11.95, 11.85 x 11.95 and 11.95 x 11.85. In detailing these, I am going to take a slightly unorthodox approach in that I am not going to start with the basic untagged stamp. Instead, I am going to begin with the tagged stamps, and those on hibrite paper. The reason is that I expect that there will be certain shade, paper and gum characteristics that are unique to printings made from the time periods while these other stamps were printed. My hope is that I can use what I learn from these stamps to help sort the sequence of printings out for the untagged stamp. 

The Hibrite Paper Stamps - Unitrade 454ii and 454pii

Paper

Unitrade lists the paper of these stamps as hibrite. While it is certainly true that it appears hibrite when compared to the dull and low fluorescent papers, it is not the absolute brightest on the scale, and consequently, I would tend to classify is as more of a high fluorescent than a hibrite paper. In ordinary light, it still has a fairly creamy, off-white appearance, though less so than the original dull papers. The picture below shows an example of the untagged block and a single tagged with the Winnipeg centre bar:

As your can hopefully see from the picture, the appearance under UV light is a mottled bluish white. In reality, it is a little brighter than the picture shows, but it definitely appears bluish. 

For both the tagged and untagged stamp, the paper appears quite distinctly ribbed, in the horizontal direction as shown in the above scan. Sometimes the ribbing is more distinct, and sometimes less, but it is always visible. The direction of the paper weave on all the stamps I have examined is vertical, i.e. mint stamps will curl from side to side. The printed side of the paper appears smooth, with a highly porous surface when viewed under 10x magnification. 

Shades

I have found a total of three very close shades on these stamps. So far, only one of these shades has been found on the tagged stamp, but all three have been noted on the untagged stamp. These three shades are shown in the scan below:

It is a tad difficult to see on this sized scan, but if you carefully compare the stamp on the left with the one on the right, you can see that there is definitely more red in the stamp on the left, whereas the stamp on the right is more of a pure brown. The middle stamp is very, very close to the shade on the left, but is just a touch duller. Let's take a look at each of these individually and see how they compare to the Gibbons colour key. 

This shade is an almost perfect match to Gibbons reddish brown in normal light. Under UV, it appears black brown. So the ink used is transformative. 

This is almost an exact match to Gibbons's chocolate shade in normal light, however, there is a slight hint of red to the colour. Under UV, the colour again appears black brown, so that the ink used is transformative. 

This is also a near exact match to Gibbons's chocolate, but is deeper. Under UV light, the colour appears black brown. So again, the ink is transformative. 

Gum

The gum on these stamps is a deep yellowish cream and is quite shiny. I would classify the sheen as glossy to high gloss. I have seen both the completely uniform smooth gum and gum that shows tiny vertical blemishes, which I refer to as the streaky dex gum. 

Appearance of the Tagging

The tagging on these stamps is very difficult to see, both in normal light, and under UV. The above tagged stamp shows a very light yellow vertical band that starts just left of the "P" of "Postage" and ends just past the "G" of "Postage". It is much, much lighter than the earlier Winnipeg centre bar tagging, which was dark yellow by comparison. Under UV light, the bars appear a light brownish yellow, and there is no afterglow whatsoever, when the lamp is switched off. Again, that stands in contrast to the earlier Winnipeg centre bar tagging, which usually gives a 1-2 second afterglow after the UV lamp is switched off. 

The scan below shows the difference in appearance between these tagged stamps and the Winnipeg centre bar tagged stamps on the dull paper:

Note how much more difficult it is to see the tagging on the hibrite paper example. 

Plate Blocks

There are to my knowledge, no plate blocks of either the untagged stamp, or the tagged stamp. They are only available as blank corner blocks.

Bringing it All Together

Given that I have found three shades of the untagged stamp and only one of the tagged stamp, it raises the question of whether the tagged stamp can also be found with the other two shades. According to Unitrade, the untagged stamp was first issued in June 1971, whereas the tagged stamp was issued in October 1971. Given that Ottawa tagging was introduced in December 1971, I would expect that the tagged stamp had a very short period of usage, and had many less printed. This I would expect there to be fewer shades of it as compared to the untagged stamp, which would have been in use longer. So I will assume that there are two shades of the tagged stamp, but not 3. I have only found the one paper, and two types of gum. I have found both 11.85 and 11.95 x 11.85 perforations, which indeed suggests that all four perforations will exist with all varieties of stamp. Thus there should exist 16 varieties of the tagged stamp and 24 varieties of the untagged stamp as follows:

1. Tagged in the reddish brown shade, with 2 types of gum and 4 perfs each = 8 stamps.
2. Tagged in the second shade (1 of the 2 described), with 2 types of gum and 4 perfs = 8 stamps.
3. Untagged in reddish brown shade, with 2 types of gum and 4 perfs each = 8 stamps.
4. Untagged in deep reddish chocolate, with 2 types of gum and 4 perfs = 8 stamps.
5. Untagged in deep chocolate, with 2 types of gum and 4 perfs = 8 stamps. 

So, in total there should be 40 possible varieties of these stamps. Given that the corner blocks can be found with wide selvage when taken from the outer panes in the complete sheet, or narrow selvage, when taken from the inner panes, or mixed wide and narrow selvage, this means that there should be 480 = 40 x 12 different corner blocks that can be collected for these stamps. 

The Winnipeg Centre Bar Tagged Stamp on Dull Paper - Unitrade 454pi

According to Unitrade, this stamp was first issued in December 1968, so it should differ quite markedly from the other tagged stamps. Sure enough, it does differ, both in shade, the appearance of the paper under UV, and the appearance of the tagging. 

Paper

All of the stamps I have examined with this tagging are printed on a vertical wove paper that has a very smooth finish. Under 10x magnification, you can see very fine curled indents on the paper surface from the paper fibres, but the paper lacks the porous appearance that the later hibrite paper has. There is no significant ribbing visible when the stamp is viewed from the gummed side. Under UV light, the paper appears as shown above: a dull fluorescent brownish grey colour. A few of the blocks I looked at did have maybe 1 or 2 stray fluorescent fibres in the paper of 1 stamp, but I have not yet found any paper containing any regular concentration of fluorescent fibres. 

Shades

I have found two shades of this stamp, which would appear to correspond to two different printings. The tagging on these also differs, as I shall explain in a minute as well. The block on the right is printed in the deep chocolate shade that we saw with the hibrite stamps above. The block on the left lacks the reddish tone to the brown and is closest to Gibbons's deep brown. Under UV light, both inks appear deeper, but not another shade or colour entirely. Therefore the inks used to print these stamps are non-transformative. 

Gum 

The gum on these stamps, like the stamps on hibrite paper is a deep yellowish cream, but there is a bit more yellow to the cream. The gum is also less glossy, being more of a semi-gloss sheen. I have found both the smooth, even texture, and the streaky gum described earlier. 

Appearance of the Tagging

The tagging found on this stamp exhibits two differences. The first is the intensity of the bands as seen in normal light. The scan above shows these two differences clearly:

1. On the left we have the deep yellow bands.
2. On the right we have lighter yellow bands.

Under UV light, the colour of these bands is seen to vary. I have found three variations as follows:

1. Deep, yellow.
2. Greenish yellow.
3. Bluish white.

The picture below shows the greenish yellow and bluish white types. I did not include the deep yellow because the difference between it and the greenish yellow will not show up clearly in this type of picture. However, I assure you that you will be able to see the difference quite readily when you have both types:

On the left we have the greenish yellow, and on the right, the bluish white. The bluish white seems to correspond to the less deep bands, and is much less common than the greenish yellow and bright yellow, based on my examination of several thousand stamps. 

Plate Blocks

As with all the tagged stamps of this issue, there are no inscription blocks, and just blank corner blocks. The blank blocks can be collected with ether wide selvage from the outer corners of the outer panes of the printer's sheets, or with narrow selvage, from the centre panes, or mixed wide and narrow selvage, from the inner corners of those outer panes. So even though collectors typically collect 4 corners, it is really possible to collect 12 different positions. 

Bringing it All Together

Again, as with the hibrite paper stamps, there seems to be only one type of paper. There are two shades, two types of gum and three types of tagging. I only found perf. 11.85 on the two blocks I checked, but I would expect that all four perforations should exist on these too. Thus there should be 2 x 2 x 3 x 4 = 48 different possible stamps, and 48 x 12 = 576 different possible corner blocks that can be collected:

1. Deep chocolate with yellow tagging: 2 gums and 4 perfs. = 8 stamps.
2. Deep chocolate with greenish yellow tagging: 2 gums and 4 perfs. = 8 stamps.
3. Deep chocolate with bluish white tagging: 2 gums and 4 perfs. = 8 stamps.
4. Deep brown with yellow tagging:  2 gums and 4 perfs. = 8 stamps. 
5. Deep brown with greenish yellow tagging: 2 gums and 4 perfs. = 8 stamps.
6. Deep brown with bluish white tagging: 2 gums and 4 perfs. = 8 stamps. 

The Winnipeg 2 Bar Tagged Stamp - Unitrade #454p

According to Unitrade, this was released in February 1967, and would have been in use until the centre bar tagged stamp replaced it in December 1968. So it was in use for a a little under 2 years. Again, there are some marked differences between this stamp and the others. Most notably, the colour, which is either deep brown or light sepia. There is no red at all in the colour, whatsoever, in any of the stamps I looked at. As with the other tagged stamps there are differences in the appearance of the tagging and the paper as well. 

Paper

There are four types of paper that I have found on this stamp: two that most closely fit Unitrade's definition of NF and two that fit Unitrade's definition of DF. As with the Winnipeg centre bar stamp, the paper has a highly finished surface and is vertical wove. Again, there is sometimes very weak horizontal ribbing visible on the back, but not usually. In normal light, all of the papers have a creamy off-white appearance. 

The pictures below show these four types of paper:

The dull fluorescent paper is generally either a light greyish colour like the block on the left, or it is a greyish white colour as shown by the block on the right.

The picture below shows the two non-fluorescent papers:

The block on the left is a brown colour and the block on the left appears bluish violet. This affects the appearance of the tagging, making it appear more bluish than it really is. 

None of the papers I looked at contained any fluorescent fibres. 

Shades

I have found two distinct shades on this stamp as shown on the above two blocks. The block on the left is printed in deep brown ink. The block on the right is printed in a deeper ink that is closest to Gibbons's blackish brown, but is a bit lighter. Under UV light, neither ink changes colour, so the inks used here are non-transformative. 

Gum

The gum found on these stamps is, once again, deep brownish cream, with a semi-gloss sheen. Both smooth and streaky versions are found. 

Appearance of Tagging

The tagging bars differ in appearance between printings, just like the other tagged stamps. I would note that the tagging bars on this stamp are generally quite a bit lighter in appearance than the centre bar tags. On some printings, the bars are so light, as to be almost invisible to the naked eye. The block on the left, shows clearly visible yellow tagging bars, that are nonetheless, not dark in appearance. In contrast the tagging bars on the right hand block are barely visible. 

Under UV light the colour of the bars does appear to vary, with some stamps having bars that appear greenish yellow and others that appear more bluish white. I believe that this difference is caused more by differences in the appearance of the paper under UV, rather than any difference in the taggant compound itself. However, the spacings between the tagging bars does vary in some panes. The normal spacing is 16 mm. However, on some panes, the spacing between the outer and middle bars is 15 mm. The picture below shows the difference between these two spacings:

The top block, printed on DF paper, shows the 15 mm and 16 mm spacings, while the bottom block on NF paper shows the 16 mm spacing. As far as I know, the narrow spacing is only found on blocks from the left corners. 

Curiously, Unitrade does not list the Winnipeg 2 bar tagging on NF paper, even though it does clearly exist. 

Bring it All Together

Here, we have 4 papers, 2 shades, two tagging spacings, though one only occurs on half the possible block positions, two types of gum and 4 perforations. This should give 4 x 2 x 2 x 2 x 4 = 128 possible stamps, and ((12 x 24) + (6 x 8)) x 4= 1,344 possible corner blocks:

1. Dull fluorescent greyish paper: 2 shades, 2 gums, 2 spacings, 4 perfs. = 32 stamps.
2. Dull fluorescent greyish white paper: 2 shades, 2 gums, 2 spacings, 4 perfs. = 32 stamps.
3. Non-fluorescent brownish paper: 2 shades, 2 gums, 2 spacings, 4 perfs. = 32 stamps.
4. Non-fluorescent bluish violet paper: 2 shades, 2 gums, 2 spacings, 4 perfs. = 32 stamps.

The Precancelled Stamp - Unitrade 454xx

This stamp is only listed on DF paper, but again, I have found that it clearly does exist on both DF and NF papers. 

Paper

I have found 4 papers for this stamp, that are very similar to those found on the winnipeg tagged stamp. However one of the greyish white DF papers contains very few low fluorescent fibres in the paper. I had not found this type before on the other tagged stamps. Similarly, I have not found the brownish NF paper for this stamp either. 

Shades

I have found two shades of this stamp:

1. Deep brown.
2. Blackish brown.

These are the same two shades that we saw with the stamps tagged with Winnipeg 2-bar tagging. This tends to suggest that most of the precancelled stamps with dextrose gum were printed before December 1968, The scan below shows these two shades:

The deep brown is shown on the left, while the blackish brown is shown on the right. 

Gum

The gum on these stamps is a deep cream with a semi-gloss to high gloss sheen. Both smooth and streaky versions have been seen. 

Plate Blocks

Like the tagged stamps, the precancelled stamps were not issued with plate inscriptions. Instead a warning to the effect that these stamps are only to be used as authorized are placed in the left and right sheet margins reading downwards and facing sideways. Usually, the full warning strips of 20 are collected intact, but corner blocks, with and without the warning text can be collected. As with other blank blocks, up to 12 positions are possible. 

Bringing it All Together

Given that I have found 4 papers, two shades, two types of gum and four perforations, there should be up to 4 x 2 x 2 x 4 = 64 different collectible stamps, and 12 x 64 = 768 possible corner blocks. 

The Untagged Sheet Stamp - Unitrade 454

This is the most complicated of the stamps because it was in use from February 8, 1967 until the untagged PVA gum printing replaced it in December 1971, though the hibrite stamp appeared in June 1971. 4 different plates were used to print the stamps and if memory serves me correctly, plate 3 came into use in early 1970, while plate 4 came into use in late 1970-early 1971. So my starting point, must be to look at these plates first, and see which shades, paper and gum types are to be found. Then I can look at the plate 2 and plate 1 printings. 

Plate 4 Printings

Paper

I have found two types of dull fluorescent paper on the plate 4 blocks that I examined:

1. Bluish white with a very sparse concentration of low fluorescent fibres in the paper.
2. Greyish white with no fluorescent fibres visible.

Like the other stamps examined so far, the paper generally is vertical wove, has a very porous surface, like the stamp on hibrite paper, and does not usually show visible ribbing on the back. In normal light, the paper has a creamy, off-white appearance. 

Shades 

I have identified three shades for the stamps printed from this plate:

1. Deep brown
2. Deep chocolate
3. Chocolate

The first two of these shades are found on some of the other stamps, but the chocolate shade is entirely new. The scans below show each of these shades:

Deep brown

Deep chocolate

Chocolate

Under UV light, the inks all retain their essential character, though they do appear darker, so they are non-transformative.

Gum

I have found three types of gum on these printings. All of them are a deep cream colour and have a semi-gloss sheen:

1. A completely smooth gum.
2. A streaky gum with strong vertical streaks.
3. A blotchy gum that has the appearance of being "sponged" on. This third type of gum is not found on the plate 1 and plate 2 printings, so it can be used to help identify singles printed after 1969. 

The high resolution scans below show these three types of gum:

Smooth gum. 

Streaky gum with vertical streaks

Blotchy gum

Bringing it All Together

I assume that all three shades identified above, exist with both paper types and all three gum types, though a detailed study would be necessary to establish this for certain. Assuming though, that all shades, papers and gums exist with all perforations, then there should be 3 x 2 x 3 x 4 = 72 different stamps and 4 x 72 = 284 possible plate blocks. Again, there should be blank field stock blocks with this plate, that exist in 12 positions, which means that one could collect up to 72 x 12 = 864 blank blocks. Some of these may be difficult to distinguish from plate 1 and 2 printings, as all three shades found on this plate are also found on plate 1 and 2, but generally only with the smooth gum. Blocks that have either the blotchy gum or the vertically streaky gum will generally not be from either plate 1 or plate 2. Plate 3 also comes with blotchy gum and is found printed in deep chocolate. Some blocks from this plate like this that are blank will not be distinguishable from blank plate 4 blocks when the same type of DF paper was used in printing them. 

Plate 3 Printings

The plate 3 blocks that I examined are all printed in deep chocolate. The gum is either blotchy as shown above or the perfectly smooth gum. The colour of the gum is deep cream and the sheen is semi-gloss to glossy. Again, the paper is quite porous when examined under 10x magnification, it is vertical wove, and shows no significant ribbing on the back. Under UV light, it generally appears dull bluish white. So it only comes on dull fluorescent paper, just like plate 4. The paper can either be found without any fluorescent fibres, or a few low fluorescent fibres in the paper. However, the bluish white colour and greyish white colour is quite unlike what is usually found on the plate 1 and 2 printings. 

So, with 1 shade, two gum types, and two paper types, there should be 4 different stamps and 16 different plate blocks. Again, blank field stock blocks also exist, and there should be up to 12 positions, so 48 different blank blocks for this plate. Again, though, it may be difficult to distinguish between blank blocks from this plate and those from plate 4 and some printings from plates 1 and 2. Generally, the paper will eliminate plate 1's and 2's since the DF paper of plate 3 and the porous surface finish are completely different from plate 1 and 2 stamps. But plate 4 stamps with blotchy gum and plate 3 stamps with blotchy gum, printed in the same deep chocolate shade, on the same DF paper, will not be distinguishable. Now, in practice, it likely will not be possible to distinguish plate 3 and plate 4 singles, though those stamps on paper giving a dull fluorescent bluish white reaction with no fluorescent fibres might be identifiable as only coming from plate 3. More study is required to establish this with certainty. 

Plate 1 & 2 Printings

These plates were in use from February 1967 until 1970 - just over 3 years. So the printings from these two plates should display the largest range of papers, shades and gum types. 

Papers

As Unitrade states, there are two classes of paper for these stamps: the dull fluorescent papers, which comprise the basic #454 listing in Unitrade, and the non-fluorescent papers, which comprise the Unitrade 454i listing, though as we shall see, most of these have no fluorescent fibres, which makes Unitrade's listing confusing. 

I have found the following dull fluorescent papers:

1. Dull fluorescent ivory white under UV, with 1-2 low fluorescent fibres visible.
2. Dull fluorescent bluish white under UV with a very sparse very few high fluorescent fibres.
3. Dull fluorescent greyish white under UV with no fluorescent fibres.
4. Dull fluorescent greyish white under UV with very few fluorescent fibres.
5. Dull fluorescent greyish under UV with no fluorescent fibres. 

As far as non-fluorescent papers go, I have found four, all of which show no fluorescent fibres at all:

1. Non-fluorescent violet grey under UV.
2. Non-fluorescent blue grey under UV.
3. Non-fluorescent grey under UV.
4. Non-fluorescent yellow tinged grey under UV.

So, all in all, there are at least 9 different paper types for 454 and 454i. I only had a very limited range of 1c stamps to work with here, and so I suspect that there are many more variations than just this. But for now, this is plenty. Generally speaking these papers have an extremely fine surface finish on the printed side of the paper, with no surface porosity at all when viewed under 10x magnification. This is especially the case for some of the non-fluorescent papers, which can sometimes appear to be coated, with some type of non-fluorescent coating. The weave direction is almost always vertical, and some copies sometimes show a fine hoizontal ribbing on the gummed side, though it is nowhere near as strong as what we saw on the hibrite paper stamps. 

Shades

The shades found on these stamps run the gamut from blackish brown all the way to chocolate:

From the top left to the bottom right we have:

1. Blackish brown.
2. Lighter blackish brown.
3. Very deep brown.
4. Deep chocolate brown.
5. Deep brown
6. Chocolate

The stamps on non-fluorescent paper tend to be found in the first three shades, while the stamps on dull fluorescent paper are found in all shades shown here. I suspect that if one looks hard enough, all papers exist in all shades, but a full scale study would be required to establish this for certain. For the moment, I will assume that all shade, paper, gum and perforation combinations exist. 

The following close up scans will hopefully help you distinguish the shades more readily:

Blackish brown

Lighter blackish brown

Very deep brown

Deep chocolate brown

Deep brown

Chocolate

The shades can appear quite similar to one another when viewed individually, but when you compare them to one another the differences become apparent. The chocolate browns have some red undertone to them, whereas the blackish browns and deep browns do not. Under UV light all the inks retain their essential character, appearing as merely darker versions of themselves. Thus, these inks are non-transformative. 

Gum Types

I have found essentially 4 types of gum on these printings. All the gum is a deep cream to yellowish cream:

1. A thinner smooth cream gum with a satin sheen.
2. A  smooth cream gum with a semi-gloss sheen (most common).
3. A streaky cream gum with a semi-gloss sheen (next most common).
4. A smooth cream gum with a high gloss sheen. 

The scans below show these gum types:

The satin gum. Note the completely even colour and fine crackly pattern.

The semi-gloss gum. Again, the colour is even, with a fine crackly pattern.

The streaky gum. If you look closely you can see the light and dark patches in the gum that cause it to appear streaky.

The high gloss gum. The colour appears slightly deeper and less crackly in the scan. 

Bringing it All Together

So far, for these printings, I have identified 9 paper types, 5 shades and 4 gum types, as well as the general observation that there could be as many as four different line perforations. Thus, the number of potentially identifiable varieties from plates 1 and 2 is:

9 x 5 x 4 x 4 = 720! 

Given that there are 2 plates and 4 corner positions for each plate, there can be 8 plate blocks for each variety and up to 12 blank corner blocks. So one could collect 8 x 720 = 5,760 plate blocks and up to 8,640 blank corner blocks, that could all potentially be different. Given the immense print quantity, it is indeed possible. 

Some Sorting Tips

If  you do not have a UV lamp handy, it pays to be aware of some general tips to help you sort your stamps:

1. Check the shades first. If you see reddish brown, that shade is unique to the hibrite papers, and it is very likely a HB paper. If there is strong horizontal ribbing visible on the gummed side, then it almost certainly is. 

2. If the shade is a chocolate or deep chocolate brown, then it could be from any of plates 1 through 4. In this case, check the paper surface. If it appears porous under magnification then it is either a plate 3, a plate 4 or a highbrite from plate 4. If it has a smooth finish it is from either plate 1 or 2. If it is a blackish brown shade then it must be from plate 1 or 2, and is quite likely to be on non-fluorescent paper. 

3. Check the gum. If the gum is blotchy in appearance, then it must be from either plate 3 or 4. If it has a thin appearance with a satin sheen, it must be from plate 1 or 2. If it has strong vertical striations and not merely the small uneven spots, then it is the streaky gum from plate 4. 

The above tips will help you pre-sort your stamps into groups, which you can then check more carefully with your UV lamp later.

If your stamps are used, the question is: how will you know that they are not PVA gum printings with no gum? The answer is that the shades will be completely different for PVA gum stamps as is the paper. You can tell PVA gum paper, even without a UV lamp. I will explain how in my next post. 

This concludes my discussion of the sheet stamps of the 1c Northern Lights and dogsled design, printed with dextrose gum. Next week, I will look at the stamps printed with PVA gum. Hopefully this post will have given you some appreciation for the vast scope that is possible with this issue and shows you that Unitrade only scratches the surface and provides a broad overview of what actually exists.