Despite this expansion in coverage, there is still, in my humble opinion, much inconsistency in the descriptions of papers, as well as some confusion when it comes to describing fluorescence levels. There are also other instances where very subtle, but real varieties are getting overlooked because the current nomenclature to describe the papers cannot accomodate the varieties, so that they get lumped in with other paper types.
The tricky part to today's post will be getting illustrations of the varieties that show the fluorescence well. Because I have to use my ultra-violet light to show the paper types, I cannot use my scanner, and have to rely instead on my digital camera. This does not have the best resolution, but I will try to take the best pictures that I can, and hopefully they will be of sufficient clarity to illustrate what I am talking about here.
Points of Confusion in Describing Fluorescence and Attributes
As my pictures will show, the nomenclature in Unitrade that has been used to describe fluorescence is confusing because quite often two very similar stamps will be described differently, while the same basic descriptor, such as "F" for fluorescent, LF for low fluorescent, or HB for hibrite, can look very different on different stamps. This is not a desirable state of affairs for someone who is trying to properly classify their stamps, and who do not have the benefit of a large reference collection against which to compare their stamps. In any event, it should not be necessary to have such a collection on hand. A good system of nomenclature should enable a complete novice to properly identify and classify their stamps using straightforward descriptions.
Why does this confusion arise?
The main reason is that there are several dimensions to paper fluorescence:
- The brightness of the paper under long wave ultraviolet (UV) light.
- The colour of the paper under UV.
- Whether of not the paper is of uniform, or compound fluorescence.
- Dead paper, which is at the lowest end of the scale.
- Non-fluorescent (NF) paper.
- Plain or dull paper (DF).
- Low-fluorescent (LF) paper.
- Medium-fluorescent (MF) paper.
- High fluorescent (HF) paper.
- Hibrite paper (HB), at the highest end of the scale.
These stamps to my eyes are both low fluorescent overall, although Unitrade classifies the one on the right as medium fluorescent. The stamp on the left is dull bluish white while the one on the right is a clear bluish white.
- SF, which stands for speckled fluorescent has been used to describe paper like the above.
- LF-fl has been used to stand for low fluorescent flecked, which is how the above paper has often been described.
- F, which stands for fluorescent has also been used to describe the above paper.
- DF-fl stands for dull fluorescent flecked, for the fibres.
- Gr. stands for greyish, which is the colour of the paper under UV.
- MF refers to the fluorescence level of the fibres embedded in the paper,
- LD stands for low density, which means that the fibres cover the entire surface of the stamp, lightly, such that there is a lot of space between the fibres.
- LF-fl stands for low fluorescent, flecked, to describe the overall fluorescence, and the fact that there are brighter fibres embedded in the paper.
- white, describes the colour of the paper under UV.
- HF refers to the fluorescence level of the fibres embedded in the paper.
- S stands for sparse, which means that there is a light sprinkling of these fibres across the surface of the stamp, but the fibres are not at all dense, and there may be areas of the stamp where there are no fibres at all.
- The brightness of the fibres.
- The concentration of the fibres.
- 1 or 2 - No fibres at all visible, except literally just one of two lone fibres.
- VVS - very, very sparse - fewer than 10 fibres visible.
- VS - very sparse a very light sprinkling with no fibres at all on 50-75% of the surface area of the paper.
- S - sparse - a light sprinkling of individually visible fibres visible on 50-75% of the stamp surface. Large gaps are seen between individual fibres.
- LD - low density - a uniform coverage of individually visible fibres across 100% of the stamp surface.
- MD - medium density - a uniform coverage of fibres that while idividually visible, are heavily concentrated, and often appear to merge together.
- HD - high density - almost looks as though it is uniform fluorescence, but on closer examination it is apparent that there is actually an extremely dense concentration of fluorescent fibres that are so close together, you often need a loupe to see them.
The above picture shows four coil pairs for the 8c library coil. Three of these are general tagged: the left pair, and the two pairs on the right. All four of these pairs contain some fluorescent fibres, but in varying amounts and brightness:
- The first pair has a very sparse concentration of low fluorescent fibres. The overall paper is a dull fluorescent greyish, so that Unitrade would classify this as LF/fl because of the fibres. My name for this, given the above naming convention would be DF-fl, Gr., LF, VS.
- The second pair also has a very sparse concentration of low fluorescent fibres. However, this paper is a dull fluorescent greyish white. Unitrade will likely classify this as "F" paper. My name for this is DF-fl, GW, LF, VS.
- The third pair has a sparse concentration of medium fluorescent fibres. The paper is low fluorescent, bluish white. Unitrade will likely classify this as MF. My name for this paper would be LF-fl, BW, MF, S.
- The fourth pair has a low density concentration of HF fibres. The paper is a medium fluorescent bluish white. Unitrade will likely classify this as HF, but my name for it is MF-fl, BW, HF, LD.
Here is a close up shot of the last two papers:
Here you can see that on the left pair there is a light sprinkling of fluorescent fibres across the surface of the stamp, but there are large areas of the stamp that have no fibres, Whereas on the right pair, there is a fairly even distribution of the fibres, right across the surface of the stamp.
Here is a close-up of the first two pairs. As you can see on both, there are still quite a few fibres visible, but they are spread very, very far apart across the entire paper surface. This is what I call very sparse.
Unitrade lists the 6c black CBN die with precancel and general tagging as being on either F, LF or MF paper, while the untagged precancel is listed as LF. The non-precancelled stamps with 4 mm general tagging are listed as being either NF, LF/fl or HF. Clearly, at first glance the first two stamps and the right stamp appear similar, which would suggest LF, even though Unitrade uses LF for two of them and LF/fl for one. The third stamp is clearly what Unitrade classifies as MF.
Here is the common, plate 3 PVA gum printing of the 15c that Unitrade classified as F paper. It clearly is no brighter than LF overall and is actually DF-fl, GW, LF, LD.