Conservation Issues: Foxing and Water Stain

The small brownish stains known as foxing are not well understood, but they seem usually to be the result of mold growth. Another kind of foxing (typified by a light area in the middle of each brown spot) may be the result of metal inclusions in the paper, or even of old paste residue. The growth of foxing can often be arrested in a low humidity environment, but it does not always respond to standard cleaning treatments. This print has also been damaged by water, which has left a stain over the affected area of the paper.