Love Flourishes 5255, Overall Tagged Or Prephosphored Paper

Rudy de Mordaigle writes a column, Modern U.S. Varieties, in the publication U. S. Stamp News. In the August 2019 issue he published a response to my inquiries on his conclusions as to the type of tagging used on the Love Flourishes issue. I have a lot of respect for his expertise and opinion, but I am not convinced of his conclusion that it is printed on prephosphored paper. I thought I would share my reasons why I am still of the opinion that it is Overall tagged since this is a strong area of interest for me.

The official USPS bulletin describes the Paper Type as Phosphor Tagged Paper, Overall. I am not one to trust the USPS descriptions totally as they are not consistently described. So I always check them my myself. If I still have questions as to the tagging type when using SW UV and a 10x loupe, I have a nice microscope I can resort to.

Below are some pictures taken of the two 5255 types under higher magnification using my optical microscope. The first is several images of the greenish-yellow version in different location. The second is a side by side of the bluish white on left compared to the greenish-yellow on the right.


You can see from the images that the taggant appears on top of the printed areas. This would make it either Overall or Block if you didn't have the selvage to view. The "O" in FOREVER illustrates this pretty clearly in the two images.

The next image shows the two 5255 varieties and the new President George Bush issue. You can see the selvage is fully tagged in both versions of the 5255. This would lead to the conclusion that it is Overall and not block tagged.

There are two reasons I included the new President George Bush issue.

First it is also printed by BCA, same as 5255 and I have the sheet showing the selvage. If you read the USPS bulletin on the Bush issue the Paper Type is described as, Phosphor Block tag. When you look at the selvage on the Bush issue you can see it is fully tagged. Maybe the sheet is block tagged before being cut into panes but you wouldn't conclude this from viewing the selvage under SW UV.

Second reason is since both are printed by BCA, I thought I would do a side by side comparison between the Bush issue and the 5255 greenish-yellow version since they look very similar under 10x. Below are those two issues under my optical microscope. Bush is on the left and 5255 is on the right. The tagging pattern looks the same and you can see the taggant over the printed image in the Bush version clearly as well.


From these images it seems pretty clear the 5255 has the taggant on top the printed image which would agree with the original USPS Bulletin description as being Overall tagged. Thoughts and feedback welcomed.

I would agree with your overall conclusion based on your images.

I also think your thoughts are good, but could you perhaps show another photo under magnification of a phosphor tagged paper, a similar part with a letter in black? This would help perhaps.

Here is a magnified example of 4860, a prephosphored paper. In this case is is a coated paper so tagging appears solid.

In the next view 5255 is on the left and 4860 on the right for comparison. If you look at the area in the red box you can see the taggant is on top of the printed dots for 5255, while the 4860 does not show the taggant on the dots. The lighter spots you see in the black dots on 4860 are gaps/voids in the inked dots.

Next image is of 5296. What is interesting in this image is that it is block tagged with the ink printed on top the taggant since it is an Intaglio (engraved) type stamp. You can see the edge of the block tag to the right of the die cut. If you didn't have the selvage you might assume it is on prephos paper. This issue like many others are printed by BCA on paper that appears very bluish and reactive under SW UV and bright white under LW UV.

Hope this helps