"Cleaning" Old Dirty Stamps

I have a question about whether and how you do remove dirt from old stamps (late '800, early '900). I've a lot of classic stamps that are in quite good shape (re perfs, etc.) but that are dirty, with black spots and so on. Time is a bad friend for everything...

Is it a good idea to try to clean these old stamps or is it better to leave them in peace?
How? a quick bath in clean water?

Best,
Gianluca

Black spots tell me it is mold......get rid of them ,so your other stamps are safe .

Hi, thank you for your feedback and sorry if my first post was misleading. I do not refer to black spots of mold. Rather, I am thinking to brown/yellow/etc. stains that are due to the stamp having incorporated dirt over the years

upload some pics?

Possibly tape or paper or toning stains?. Rismoney is correct. Show a few clear scans and the members will give their opinions as to what is best.

For stamps without gum a bath in clean water can help. You will want to use a catalog to make sure the stamps do not bleed ink in water (aliline inks). Then dry and flatten them. Try a few.

I'm a little surprised no one has mentioned dipping dirty or stained stamps in a mild solution of hydrogen peroxide and water. There is no "best" formula for this, but it's always safest to begin with less than more. Try a capful of hydrogen peroxide in a cup of water, then let the stamps soak briefly and see if that makes any difference. You should probably experiment on stamps that are expendable just in case this fades the image, but small amounts of hydrogen peroxide are unlikely to do that. I've never tried putting a stamp in only hydrogen peroxide without water, but it would be interesting to see the result.

Using bleach, by the way, is not suggested as it will surely fade the stamp and may even completely ruin it, but hydrogen peroxide is commonly used to brighten up stamps, remove small stains, and so on.

It doesn't alway work for me, however, so don't be surprised if it doesn't work for you. And be sure to begin with a very mild solution, leaving the stamps in for only a few minutes at first, then work up from there. Always rinse with clear water to remove the solution from the stamp. I've never tried soaking a stamp for a very long time, overnight perhaps, in a hydrogen peroxide solution but that would also be interesting to try on some expendable stamps just to see the result.

Good luck.

Hydrogen peroxide is a bleaching agent and it will bleach your stamp if it is too strong or if you leave it in the solution for long periods. Good stewardship is to not play chemist and best public recommendation is to use only clear, cool water.
The approach should be conservation, not restoration. The risks, including lowering value, occur with restoration processes.
Don

Hello.
Some old gum have animal components and mold grows on the back.
I use heavy washing machine bleach to remove stains, being careful not to submerge the stamp, just turn it upside down for no more than 30 seconds and rinse it with clean water right away. If it is not removed, the operation can be repeated, although it is not recommended more than 3 times. Es mejor experimentar antes con sellos comunes para adquirir destreza.
Regards.

Everyone can experiment with the material they own but in my opinion this kind of post does not reflect responsible stewardship.

Who here would want to buy bleached stamps? Bleaching chemically alters the stamps and altered stamps should be described as such in any marketplace.
Don

Without seeing some sample images, it would be premature to recommend anything at all.

And yet the method of soaking in a very mild solution of hydrogen peroxide and water is commonly suggested to lighten dirty stamps which is what OP asked about. Here are some examples of those suggestions from stamp websites:

"Another method for restoring the original colors from oxidation, or to possibly lighten age toning, is to soak them for a short while in Hydrogen Peroxide .... available at most grocery / drug stores. It works well with engraved postage stamps and with most lithographed or typographed stamps, but if the stamps are photogravure, you should be very careful. As always, TEST THE PROCESS with CHEAP stamps first."
(from "Stamp-Collecting World")

"I have two Nicaragua telegraph stamps that were discolored by the sulphurization (often mistakenly called "oxidation) and my wife has a spray bottle of 3% hydrogen peroxide from CVS. Hmmmm. An opportunity to do a little experimenting. I placed the first stamp face up in a watermark tray and sprayed lightly. In less than a minute, the original bright orange stamp color had been restored. I tried the second stamp, simply putting it face down in the few drops of liquid that remained in the tray. Again, in less than a minute, the stamp color had been restored." (in a discussion on "StampoRama")

"Yellow ink (which is also one of the ingrediants in orange ink) has a tendency to oxidize, the classic example is the 6¢ Prexie Garfield. Careful treatment with peroxide, applied lightly with a cotton swab will restore the color. You can obtain hydrogen peroxide (H202), pure peroxide has the ability, if not handled right, to blow a hole in your ceiling. Diluted Hydrogen Peroxide is obtainable from any drugstore."
(from "TheSwedishTiger.com)

And so on. I have had little success the few times I've tried soaking in hydrogen peroxide and water on a few very common stamps, so don't "suggest" this but only relate what others claim has worked for them. Anyone who decides to try should experiment first on cheap disposable stamps using a very mild solution and see if they get any results at all.

Orange or yellow stamps that have browned over time seem to be the most likely candidates for this treatment as it supposedly restores the original color. It's the browning that is not original so is the problem, and not the original color.

The chemistry of hydrogen peroxide does not require that stamps later be soaked in water since the extra oxygen in hydrogen peroxide (H202) will naturally evaporate as the hydrogen peroxide breaks down. Nor does any chemical remain in the soaked stamp to cause later problems.

I'd never suggest using bleach on stamps since it will surely damage them. There are definitely also some early stamps which hydrogen peroxide will also likely damage. Your guess is as good as mine as to which ones they are. Best practice would always be not to experiment on early stamps.

A drop of dish soap in water can also be experimented with if you wish to remove dirt from a stamp by soaking it. Dish soap breaks down dirt which is what it's designed to do as mildly as possible. Again, whether that stamp is a good candidate is very hard to know and I'd never do this on early stamps or stamps of high value.

So the working theory is "if it is on the internet, it must be true?" The three sites that you cite have plenty of incorrect information on them and I would like to avoid having unsafe information being posted here.

This community is not like a face-to-face situation where you can understand who you are talking to (i.e. level of experience), make sure that you have a 'meeting of the minds' as to using caution, use feedback to make sure that what you are saying is being taken in the right way. So I feel it is important that we ensure our posts reflect safe stewardship advice. There are literally thousands of folks who do not post here but read and use the information provided. Our concern is not for members who engage by posting and asking additional questions, the concern is for people who lurk.

I use a simple 'self check' on my stewardship posts; am I willing to put my money where my mouth is? In other words, if someone reads my post but then ruins their family heirlooms by using it, would I be willing to replace them at my cost? I assume that some folks will not use 3% hydrogen peroxide but rather walk into the drug store and grab the 10% hydrogen peroxide. I assume that most people do not know that hydrogen peroxide decomposes with exposure to light and begins to lose strength shortly after opening a new bottle (important to know when 'experimenting'... big delta between a new bottle and a opened older bottle). Since this is a public forum I assume worse case scenarios and err on the side of offering 'non-experimental', 'do not harm' safe advice.

I do agree that 'experimenting' helps grow the hobby knowledgebase. But I always consider the experience level of the original poster in these threads and in the majority of time they are nowhere near the level of hobbyist who is seeking to 'experiment' but rather they are less experienced hobbyists. It is quite unusual to have a thread which has been started by one of our more experienced members asking about the possibility of doing 'experiments'.

So in my opinion these are not the kind of threads which are good to demonstrate how clever or smart we with our posts but rather help less experienced hobbyists learn the basics of good stewardship.
Don