The Stamp Papers - Looking For A Brief History Of Stamping Pamper And Ink

Hello all,
I'm new to the game and inquiring about postage stamp paper. I'm familiar with the types of paper, i.e., wove and laid and the manufacturers American Bank Note Company, Continental and National.
However, I can't seem to find any resource on the paper outside of its description of "thick-thin" soft porous paper or hard. My Scott 184 measured .09mm thick and was wondering if this is the standard and what paper is its equivalent today, if any. The .09mm, in my research is about 100gsm paper. I came across Lalo 11416L 100 g, laid paper from Vergé De France and was wondering how closely it resembles stamp paper from the 19th century.

Also, as a lover of calligraphy, the type of ink used is a curiosity. Certainly an indelible ink, as well as the cancellations, but there seems to be nothing at all in what ink was used to print stamps via intaglio.

Looking forward to hearing from you!

How deep do you want to go?

Basic:
Fundamentals of Philately by L.N. Williams has articles on both paper and ink. This book is easily available. Or you can download the articles on paper from the American Philatelist website. The articles are in the July 1954 and August 1954 issues.

Advanced:
These articles will focus on specific stamp series and issues. For example:

Insight into Papermaking and Ink Chemistry of "I.S. Three-Cent Bank Note", Western Michigan University

Multiple articles are available in the publications of the Institute for Analytical Philately:
https://www.analyticalphilately.org

Papers and inks are a complex topic. The ink formulas were often considered to be trade secrets, so there just isn't much available.
The USPCS also has a few articles, usually on specific stamps or groups of stamps.

Like this one. https://chronicle.uspcs.org/PDF/Chr...24/13273.pdf

And an interesting example.


The one shown from the back is a 6c Justice dept card proof. Both were mailed from England in the same glassine in I think 2012?, neither had any marks on the back in the ebay listings.
The last printing of the card proofs was in 1894.

So it's likely the ink on the Post office card proof ink hadn't fully dried in well over 100 years.
I collect some odd stuff, and at first glance I was a little annoyed. Then I realized what was going on with it and didn't mind.

"So it's likely the ink on the Post office card proof ink hadn't fully dried in well over 100 years."

Not knowing anything about such classic stamps (but having read paperwork on cans of house paint over the years), let me contradict by claiming,
So it's likely the ink on the Post office card proof ink had so fully dried in well over 100 years that the binder no longer was as effective, allowing powdery residue at the surface that was impressed into back of other paper item that were pressed together in the glassine envelope in their transit to new owner.