tonyowen wrote: ↑02 Dec 2020 08:20
Out of curiosity I've done computer search for the mould/rust you describe.
The results [below] do not indicate the level of danger you infer
...
I'm confused so I'd like your opinion on the above
Well you can believe or not what you've been advised about here.
Those brown/orange spots on stamps ARE universally found and they DO spread to stamps that are clean. As to precisely what causes/spreads foxing I don't think I've ever seen a definitive proven analysis.
Just plenty of ideas and opinions. None of that is relevant, it is universally an unwanted feature that can reduce the value of any stamp to zero. From decades of experience from collectors around the world it DOES spread as well as worsen over time.
Used stamps soaked in hot water and dried in a good drying book seem to become "stabilised". Housing stamps in cheap albums, like those common Chinese ones seem to attract foxing like dog dirt attracts flies. Likewise second hand albums is bad practice.
Households with smokers and pets also introduce nasty airborne particles of biological and chemical material that is also harmful to paper. So how you house and treat your stamps will determine if it will survive years or not.
Clearly you have little understanding of stamp collecting from this thread. You need to invest time to read your ACSC to understand things like identifying Dies and constant flaws among the extensive information it provides. As Glen parrots : "Knowledge is power".
But its useless sitting in a reference book that you don't bother reading. Also search this forum for Foxing, Staining, Browning, Rusting as those brown marks have been repeatedly covered already.
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