Is This Mold Or Spores? Isolate Or Not?

Hi,

I was wondering if this stamp has been damaged with spores? Do you think I should isolate this stamp from other stamps and put it in a dedicated pocket/envelope? I was told this was the first issue and the gum contained too much of the starch (not sure this is the correct word). The stamp is of early 1940s (USSR).

Thanks in advance.

Opinion.
Gum disturbance from a humid environment, damp album page or glassine.
I find with mine, a soak in cool clean water, rids the damage, providing the new environment is good.

I have had duplicate with similar damage, remain OK for years in
the duplicate box providing again, the environment is dry and stable.

Still not a good look, use as space filler till clean ones arrive.

Damage like this usually starts at the fine hairs of the perforation teeth, or at the gum.
Good Luck.

I collect Russia and had never heard the starch thing before.

Well, Russian stamps before 1960 had an organic gum applied to it, not sure if starch was one of its components though. I agree it's certainly a damage but the question is rather if this is kind of foxing, mould, spores - something that can move to other stamps or if this is a permanent issue, not spreading further.

akommar - not just Russian (classic) material.... it is problem with all stamps made pre or post WWII period! Organic material used in glue production, with a lot of wood pulp in making paper .... so over time, fungus will do the job!

Auction houses and stamp dealers call this foxing when they sell you the stamp. And when they have to buy it, it's mold.

You have to treat this like it is rust or mold. Sequester.

I always thought foxing left more cleary defined spots almost like splashes of a browny rust colour and from paper conservation texts I understand it is caused by traces of iron or iron salts in the paper. it is a purely chemical reaction of iron in microscopic traces on the paper getting moist and becoming rust.

lways thought foxing left more cleary defined spots almost like splashes of a browny rust colour and from paper conservation texts I understand it is caused by traces of iron or iron salts in the paper. it is a purely chemical reaction of iron in microscopic traces on the paper getting moist and becoming rust. - It can be. But sometime it is not and the rest of your album or stamps can get a rust color. It's basically a crap shoot. I don't risk my collection with foxing.