How To Distinguish 32c Maple Leaf Coil Stamps

area66 got a point by showing the glue side, unitrade page 231 states that it is impossible to differentiate them if they were USED copies, glue must have a key role. On the other hand, it is two different paper compagnie.!! there must be a difference in the paper production.

I think it will be very difficult to use fluorescence to separate the papers or surface colour.

When I worked with the paper industry for a while the manufactures were, amongst other things, interested in the appearance of the paper in daylight.

To this end they added varying amounts of fluorescent brightener to each batch depending on the pulp they were currently using. They did not bother about the resultant appearance under UV light only day light. This was not stamp paper but I am sure the principle is the same.

This is the reason I do not assign any significance to the different grades of fluorescence that stamps can show.

These stamps are now over 35 years old and who knows how the paper appearance may have changed in that time given that they would not have been stored under any controlled conditions.

AQ

AQ

Reviving this thread, as I have arrived at this issue in the process of laying out the pages for my Canada collection.

On my pages I have been including both Unitrade and Gibbons numbers, and with the Artifacts low-value definitives from 1982-1987, the Unitrade Clark Paper listings correlated based on issue date information with the "coated paper" listings for these items in Gibbons

Does anyone know if Clark paper issue are always on coated paper? If this is the case then the difference between the two papers could be that Abitibi-Price is uncoated paper (at least on the Artifact Definitives of this era) while Clark paper is coated.

Unitrade is not much help since it doesn't mention whether papers are coated or not in the way that Gibbons does. However, Abitibi-Price and Harrison equated to ordinary paper listings in Gibbons for the Artifact defins, while Clark and Rolland equated to coated paper listings in Gibbons - based on dates of issue listed in Gibbons and Unitrade.

Note, Gibbons does NOT list a coated paper version of the 32c Coil, only an ordinary paper version, but who is to say a coated paper version might have escaped their attention.

Another tidbit that may help, according to Yvert, the Clark paper issue is printed on a "Brilliant White" paper - so a paper much whiter than the Abitibi-Price paper.

For 951, any used copies dated before Feb 15, 1984 which is when 951iii was first issued.

951/951iii