From wikipedia:
Quote:
Foxing is a term describing the age-related spots and browning seen on vintage paper documents such as books, postage stamps, certificates, and so forth. The name may derive from the fox-like reddish-brown color of the stains, or the rust chemical ferric oxide which may be involved. Paper so affected is said to be "foxed."
Although unsightly and a negative factor in the value of the paper item for collectors, foxing does not affect the actual integrity of the paper.
Foxing also occurs in biological study skins or specimens, as an effect of chemical reactions or mold on melanin.
Other causes of age-related paper deterioration include destruction of the lignin by sunlight and absorbed atmospheric pollution, typically causing the paper to go brown and crumble at the edges, and acid-related damage to cheap paper such as newsprint, which is manufactured without neutralising acidic contaminants.
Posted 02/14/2012 8:36 pm
Haven't a clue what that would mean. The stamp did appear to have a stain on the front that may have been made by whatever hinging had been used in the psat. Anyone familiar with this term "foxing"?
