foxing

Foxing refers to brownish spots that appear on old paper. This discoloration is a common issue in art conservation, particularly with prints, drawings, and manuscripts on paper.12

These spots can result from a combination of factors, including metallic particles within the paper and the presence of mold. Art conservators work to reduce discolorations like foxing, as well as acidity, which can be caused by unfavorable environmental and storage conditions. While good quality paper can last for over a thousand years with proper care, inferior papers with wood pulp or fugitive media are more susceptible to deterioration. Conservators use various techniques to treat such damage, aiming to slow down the inevitable aging process.2