It is not "oxidation". It is "sulphurization". Metal oxidizes. There is no metal in the inks used to print those stamps.
It has nothing to do with the mounts or hinges. Sulphurization is caused by changing the color of the ink pigments due to air pollutants such as smog and tobacco smoke. In other words, the stamps were not properly stored.
The glassine will help prevent air pollutants get through to the stamp. A bath in hydrogen peroxide will clean the ink pigment and return it to proper color. After that, proper care (don't smoke around stamps, or work on your stamps near a fireplace that has wood burning in it, etc.) will keep the color as it should.
Thanks, Michael.
Will regular Scott or Showgard mounts protect old stamps sufficiently? Glassine squares would seem unnecessary in a non-smoking household without a fireplace. They obviously blur the design.
Assuming my 1869s are not gummed, do you recommend using hydrogen peroxide on them and, if so, what concentration?
I have used Showgard, Scott and Prinz mounts for decades. No problem. The clear front piece protects the stamp from UV light, light from the sun or lamp.
5% solution, but practice on cheapo stamps first. You do this at your own risk. If the stamp has gum, and you soak it, the gum will de dissolved. I have done this many times, and have not had any problems.
Got it.
I just read the article you referenced. I don't know why those guys wrote it like that. If it were indeed oxidation (which is rust deterioration on iron which stamp inks are not made of), putting something that is rusty in water (hydrogen peroxide is 95% water) will only make the rust problem worse, not fix it.
Oxidation explains why most of my 19th-century letters are so difficult to read, written as they were in iron gall ink. The writing in folded-up letter sheets do seem to have better contrast. I had an very early-1800s letter (since donated to my state historical society) that was quite legible except for the edges, probably exposed to a little bit of air over more than two centuries.
On the Society's post-pandemic to-do list is a transcription of that letter, a copy of which a curator promises to send me.
In chemistry class, we made black ink by creating a mixture that contained a ferris material, which is iron. The pigments in the stamp ink do not contain any ferris material.
Oxidation, usually initiated by light, can discolor paper. Both cellulose (and its derivatives) and lignin within the paper can be oxidized. In cellulose, oxidizing the hydroxyl groups to aldehydes, ketones and carboxylic acids lead to discoloration.
Thanks, responders!
After your chemistry info, my original question has been answered. Glassine squares are unnecessary, especially in quality mounts, only exposed to light if I happen to open an album page.
The Feb 8, 2021 issue of Linn's Stamp News, page 34, has a discussion on the 1869 10-cent Shield and Eagle Stamp. Because it's "subject to oxidation," the authors "recommend putting a square of glassine on top of the stamp inside the mount to prevent this."
Two questions:
Is a 152-year-old stamp going to oxidate any more than it already has?
Are they implying that the mounts we've been using on our mint and valuable stamps are non-archival?
Here's a modern stamp with and without glassine "protection:"
re: Glassined!
It is not "oxidation". It is "sulphurization". Metal oxidizes. There is no metal in the inks used to print those stamps.
It has nothing to do with the mounts or hinges. Sulphurization is caused by changing the color of the ink pigments due to air pollutants such as smog and tobacco smoke. In other words, the stamps were not properly stored.
The glassine will help prevent air pollutants get through to the stamp. A bath in hydrogen peroxide will clean the ink pigment and return it to proper color. After that, proper care (don't smoke around stamps, or work on your stamps near a fireplace that has wood burning in it, etc.) will keep the color as it should.
re: Glassined!
Thanks, Michael.
Will regular Scott or Showgard mounts protect old stamps sufficiently? Glassine squares would seem unnecessary in a non-smoking household without a fireplace. They obviously blur the design.
Assuming my 1869s are not gummed, do you recommend using hydrogen peroxide on them and, if so, what concentration?
re: Glassined!
I have used Showgard, Scott and Prinz mounts for decades. No problem. The clear front piece protects the stamp from UV light, light from the sun or lamp.
5% solution, but practice on cheapo stamps first. You do this at your own risk. If the stamp has gum, and you soak it, the gum will de dissolved. I have done this many times, and have not had any problems.
re: Glassined!
Got it.
re: Glassined!
I just read the article you referenced. I don't know why those guys wrote it like that. If it were indeed oxidation (which is rust deterioration on iron which stamp inks are not made of), putting something that is rusty in water (hydrogen peroxide is 95% water) will only make the rust problem worse, not fix it.
re: Glassined!
Oxidation explains why most of my 19th-century letters are so difficult to read, written as they were in iron gall ink. The writing in folded-up letter sheets do seem to have better contrast. I had an very early-1800s letter (since donated to my state historical society) that was quite legible except for the edges, probably exposed to a little bit of air over more than two centuries.
On the Society's post-pandemic to-do list is a transcription of that letter, a copy of which a curator promises to send me.
re: Glassined!
In chemistry class, we made black ink by creating a mixture that contained a ferris material, which is iron. The pigments in the stamp ink do not contain any ferris material.
re: Glassined!
Oxidation, usually initiated by light, can discolor paper. Both cellulose (and its derivatives) and lignin within the paper can be oxidized. In cellulose, oxidizing the hydroxyl groups to aldehydes, ketones and carboxylic acids lead to discoloration.
re: Glassined!
Thanks, responders!
After your chemistry info, my original question has been answered. Glassine squares are unnecessary, especially in quality mounts, only exposed to light if I happen to open an album page.