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Pillar Of The Community
Netherlands
813 Posts |
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Pillar Of The Community
Netherlands
813 Posts |
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Pillar Of The Community
Netherlands
813 Posts |
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Fluorescence is a matter not quite understood by philatelists!
Around 1974 Dutch collectors started to distinguish two types of paper: D [dull] and W [hibrite] for the coil stamps of the 1948-1967 period.
All definitives stamps were printed in photogravure on uncoated paper. I started to study under UV the Dutch definitives both from counter sheets, coils and booklets and I discovered 2 independent phenomena!
Before 1958 there was NO optical brightening agent added to the paper pulp, from 1958 onwards [white reacting] fluorescent fibres began to appearin a otherwise dull [no OBA] paper. The frequency [quantity per stamp] of the fibres [Leuchtfasern] was increasing in time so by 1966 there was virtually no way to tell the fibres apart.
In the mean time in 1961 the Dutch commemoratives were printed on coated paper with OBA both in the paper pulp as in the coating, no fluorescent fibres!
But also in the 1961-1967 period the intensity of the OBA of either coating or paper was increasing.
Thus, we have (in theory) a 3-dimensional space in which both the number of fibres per surface unit varies as well as the quantity of OBA substance varies in coating and/or paper pulp.
I stuck to - in 1974 my article was published - 6 levels for the uncoated papers: D [dull], V0, V1, V2, V3, W[hite] [the Dutch word "Vuil" meaning "dirty"].
In the V-range all you can do is estimating the number of fibres, realising that independently the OBA may have been added as well and may give a brighter appearance.
Already then, I had to be carefull with used/washed off stamps thst could have acquired OBA's from the enveloppes they wre on.
Later on, in the late 1980-ies, with the atention for environmental effects of the OBA's, dull paper returned [OBA-free] with a different appearance under V! Before 1958 dull meant a yellowish/brownish appearance, since the late 1980-ies it has a violet appearance as if the UV-light was reflected! This goes for both the paper pulp as well as for the coatings.
Dutch commemoratives in the 1971-1998 period were on coated paper delivered by Harrison&Sons predominantly, with a phosphoresent substance in the coating. This changed in 1998 -Harrison stopped - and since then for Dutch commemoratives Tullis Russell is the main source of paper. Still coated paper but no phosphorescence in the coating, printed bars entered the scene, and the UV-reaction of the coating was violet inert. |
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Pillar Of The Community
Canada
4521 Posts |
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I also have problems with how to judge the degree of fluorescence on Canadian stamps. I have a Lighthouse portable long-wave UV lamp which works pretty good as long as the batteries new.
Going by the chart in my 2016 Unitrade page 25 it is difficult to differentiate and compare the degree of fluorescence.
These are my stamps I picked from the chart.
NF/Dead - 505**** DULL - 400**** LF - 726**** F - 1060**** MF - 1094**** HF - 485**** HB - 497
I see no difference between NF/Dead and DULL. both measured on front
I see no difference between F and MF both back paper
I do see a difference between HF and HB whether front or back
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Pillar Of The Community
Canada
4521 Posts |
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Getting back to the $2 Scott/Unitrade 727 here are 10 used examples I have. They show a wide variance of the offset printing and also in the recess silver printing of the lettering.   |
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Pillar Of The Community
Netherlands
813 Posts |
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Quote:Paper Supplier: https://adminware.ca/checklist/chk_paper.htmFrom 1972 to early 1983, Abitibi-Price was the sole supplier of paper for Canadian postage stamps. At that time, they decided on short notice to discontinue producing this paper. For a period of time, Canada Post was forced to use paper from non-Canadian paper mills. Quite a few definitive stamps printed since 1983 have been reprinted on different paper stock. For collectors, the need to identify the different paper supplier is an important requirement (in one instance, the 74c Wapiti stamp issued is 1988, it could mean the difference between the common $2.50 stamp vs. a very rare $900.00 stamp!). In an effort to satisfy collector's needs, Canada Post has included a single-letter code as part of the plate inscription found on the imprint of each of the four corners of philatelic stock ("field" stock, or panes send to most post offices, has the plate inscriptions either trimmed off, or not printed at all).  This means the Post Office can just appease the collectors and fool the specialists in using a different type of paper when necessary i.e. in the case of running out of a particular stock and grabbing what is available.... It is VERY likely that you find different types of paper used in practice when you study used stamps! Reading the Unitrade catalogue you will see no mention of paper before mid-1983.... Since 1971 it probably was Abitibi-Price al the time but don't be surprised to find other types of paper as well :) |
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Pillar Of The Community
Netherlands
813 Posts |
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 How can someone judge this paper without knowing the specifications or without having a margin with the paper code on it??? |
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Pillar Of The Community
Netherlands
813 Posts |
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 Robin Harris [the Editor of Unitrade, Adminware] states that certain papers cannot be distinguished! Abitibi - as far as I have noticed - ALWAYS has craters at the back!  |
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Edited by Galeoptix - 02/11/2019 07:10 am |
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Pillar Of The Community
Netherlands
813 Posts |
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The Canadian Goebel-press could handle up to 3 colours in recess from one cylinder. This shows in stamp booklet with 3 denominations, but occasionally in single stamps:  Red [cycliists + 8] and black in recess plus red [Canada] in photogravure! |
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Edited by Galeoptix - 02/18/2019 4:13 pm |
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Pillar Of The Community
Canada
4521 Posts |
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Quote: How can someone judge this paper without knowing the specifications or without having a margin with the paper code on it???
Unitrade 1177 the 74c value was issued in January 1988 only on Harrison paper but Ashton Potter printed some on Rolland paper near the end of 1988 which are Unitrade 1177 iThere was a rate change to 76c (international rate) on January 1989therefore very few of the 74c were printed on Rolland paper and probably none sold at the Philatelic Center but only field stock at Post offices. Harrison paper = blue-green tinge Rolland paper = white gum |
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Pillar Of The Community
Canada
4521 Posts |
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Quote: Red [cycliists + 8] and black in recess plus red [Canada]in photogravure! Rein BABN actually used 2 colours engraved and 2 colours photogravure for Canada Unitrade 642  Engraved = black & red Photogravure = red & silver ( spokes & rim) |
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Pillar Of The Community
Netherlands
813 Posts |
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Martin,
you are right, I forgot the silver ;)
As tot he 74c Wapiti, the gum may give away the origin of the paper, but with used stamps this is of no use!
And apart from that how sure can you be that the "H" or "R" tells the truth?!
Both Rolland papers and Harrison papers may have their characteristics that are necessary to make a statement or attest....
The colour of the gum - after so many years - is NOT reliable, the structure of the papers is still telling!
Rein
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Edited by Galeoptix - 02/18/2019 4:19 pm |
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Pillar Of The Community
Netherlands
813 Posts |
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Rolland:
Parliament buildings - 1985-1988 in recess and uncoated [and how to tell Peterborough from Rolland?] Parliament - 1985-1988 in offset-litho and coated Artifacts - 1986-1987 in offset-litho and coated
at least TWO different types of paper should be involved! |
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Pillar Of The Community
Canada
4521 Posts |
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Quote: As tot he 74c Wapiti, the gum may give away the origin of the paper, but with used stamps this is of no use!
And apart from that how sure can you be that the "H" or "R" tells the truth?!
Both Rolland papers and Harrison papers may have their characteristics that are necessary to make a statement or attest....
The colour of the gum - after so many years - is NOT reliable, the structure of the papers is still telling! Rein, what you say about used copies is correct but as you can see Unitrade only lists mint values for 1177i. Below for comparison are 3 imprint blocks from the Exploration Of Canada series issued between 1986 - 1989 all printed by Ashton Potter but using 3 different paper makers.  I added a single 1177 to compare the gum. Looks pretty close to the Harrison paper and definitely not Rolland.  |
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Pillar Of The Community
Netherlands
813 Posts |
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Martin,
Gum is not enough!
They may print an "H" but that doesn't mean a Harrison paper was used! Let alone WHICH type of Harrison paper!
It will only be too easy to fool the collectors! Printers may start with a reel of Harrison to continue with Rolland for the night shift! Or the other way around!
Single stamps - without the imprint - is just as difficult as the used ones. It takes knowledge about paerp and that is what "experts'[dealers, Diplomkaufleute] usually don't have ....
Our Brixton fellow seems to be a welcome exception to that rule ;)
Rein |
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Edited by Galeoptix - Today 9 Hrs 44 Min ago |
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