Classic France, Cancellations And Shades

Sorsh,
I agree with all you wrote and undoubtedly ink formulas (and hues) changed from print run to print run. With a large enough sample size, especially plated samples and those with date cancels, it might be possible to draw some conclusions. I typically used MilSpec 105 in my QA efforts and a gross generalization of this spec pegs a sample size around 4%-5% for production runs under 100,000.
I am unsure that a MilSpec sample size could be met by a hobbyist but if the print run quantities are known and a hobbyist could accumulate a sample size around 1% it might be good enough to draw valid conclusions. I support anyone who tries to do stamp color analysis because even if a firm conclusion cannot be drawn today this preliminary work is likely to become important in the future when non-destructive chemicals analysis of the ink can be done.
Don

Don,
Just curious. What does this mean?
Eric

MilSpec is short for Military Specification (often used by many ISO complaint commercial companies). It is a generally accepted sampling size for inspection; so if you ordered parts or labels you would pull only a percentage of them to inspect.
Don

yes, knowing the numbers produced is one thing, what's preserved is definately another.

We go by approximately 5% of the earlist common values have survived, and upwards to about 15% of the high valued. As time passed, and more collectors emerged, this value increase.

owning 1% of an emmission is in generel not possible, even if you had the finance and time, how would you store such an amount of stamps in terms of studying them?

statistically we go by 2000 stamps of one specific print is equal to being able to recontructing 99.9% of a plate.

The colours within the Ceres issues are complex, and most of us will not own a copy of the 1 Fr vermilion, let alone have a group to compare. I wonder how good Mr Walske's eye was, or whether he largely relied on Brun, Behr etc for differentiating the shades.

The catalogues show relatively few colours/shades for the Sage and Blanc issues on the stock-pages, and many of these are easy to pick, recognising that fading etc may mislead in some cases.

GeoffHa - I assure you that Walske did not rely on either Brun for anything and Behr for less. Many, if not the majority, of his French stamp and postal history purchases came via the Roumet firm.

Perf12

interesting, i'd like to have access to such information, where does it come from?

The Varnish on the 20c; (Translation).
In order to avoid counterfeiting, a "safety layer" was printed lithographically. This "safety layer" was a colorless varnish (identical to the printing ink but without pigment). It did not cover the whole sheet but exceeded by a few millimeters the location of the stamps. It can be distinguished on the stamps at the edge of the sheet that have sufficient margins. Almost always colorless, it sometimes appears yellowish, greenish or brownish. The typographic printing of the stamp was improved by this layer of varnish affixed before the passage in press. Three different workshops were responsible for printing this "safety layer", which explains the differences in color, accentuated by aging.

https://www.francephilatelie.com/pr...de-technique

An example of a 20c black on white paper.Remark the difference in color of the front and back (same stamp).



http://timbresdepat.canalblog.com/a...0167560.html

In this link an example of aging on a margin copy on cover.
http://timbreceresfranc.com/france-...-sur-lettre/

thanks Perf12.

i will not venture into 1849 to begin with, simply because it'll be costly to acquire enough material.

at the moment i'm sitting with some pages of Ceres 1871 25 cent blue and looking at all these plateflaws.

from reading your page on producing 1849 ceres I can tell they were made in the same way as the danish bicolored with electroplating.

here are some rather obvious plateflaws / galvano flaws.





there are tons of these on the pages i've bought, the fun starts when you find similar ones in obvious different prints.

do you know if there are preserved full sheets or blocks, perhaps printing blocks in a museum of sorts?

The postal museum in Montparnasse has a range of material, some of which appears in the Yvert specialised catalogue. Unfortunately, it's been closed for renovation for several years (the re-opening date of 2017 was obviously over-ambitious).

https://en.parisinfo.com/paris-muse...-de-La-Poste

For YT 60 25c (Types) it is very simple.Many have plated the stamp after years of work.With this link you just look for the plate flaw.
Have fun !

http://planchage-timbres.fr/

Your last stamp with the large white dot above is found in the Ceres 25c No.60C Type III.
Variety Su42,Position 129A8.The second stamp is a constant variety in Type III: 19SU_2b (2nd state).Discovered by Suarnet.The first stamp looks like a III type,but they don't have this variety.There were several sheets. It could be a new addition….
http://planchage-timbres.fr/60C/con...es/index.php
In this web site there are a few authors who each make there contributions.It is not easy navigating inside if you cannot read French.There are sub divisions in each Type of the no.60.The first thing is identifying which type it is. I,II,or III.Then go inside the corresponding sections.

Thanks, I used the page last night, and found it was incredibly poorly made.

First of all, when you have a plateflaw, and you've established type 1-3, you still have to look through all of the positions until you find the exact one.
and if you zoom the page so you don't have to click every single stamp, once you do, the resolution is extremely poor - So a lot of zoom in and out is needed.

from what I read, the stamps were printed in sheets of 300, then cut in 2.
the page only shows stamps in position 1-150, were these 2 sheets completely identical (i doubt they were)

i figured out the 60A-C myself last night, and then the second part is to click on the D1-G1 and so on, but what do they mean?

under each you have 1-50- 51-100- 101-150, and all seem to be different.



what does 1. etat, 2. etat mean exactly, i've assumed it's how the position evolves, but is it 1st print, 2nd print? or stages, first in the emission last in the emission and so on, because some doesn't have this, and some goes all the way up to 7. etat and maybe more.

also, 60C seem to have very few informations, I assume it's because these were last to be printed, and the technique had improved = fewer flaws. (it's the same in Danish bicolour)

do you know if there have been worked on perforation machines, telling vertical rows apart as this is clearly comb perforated?



after about 15 mins of scrolling and comparing i've positioned this strip of 3, to position 11-13 under Gilles G1, however the other people working with the same seem to have varying information and apparently they don't completely agree which is what.



so, position 11-13, in what print/shade/emission/etat???

The Giro is a rating system for rarety the authors created for the stamps they are certain belong in a particular position.
The "Etat" are the small and constant différences when a paricular cliche was reproduced over time.In the 60C sheets;Type II stamps can be found in certain printings...
The letter Symbols are the differnt sheet printings.It is best reading the section "Le Tirages du 25c type" for a full discription.It is a bit complicated for sure…
So your strip of 3 looks like a 60A (TypeI).As you found; 11G1,12G1,13G1.The first stamp is
a 4th state impression.The iris is white.Right end of the mouth curved up.The 2nd one seems to be a (state I), the 3rd stamp is of a later state type I think.The upper part of the frame lines are brocken up in different segments.Exact identification needed.