Reverse foxing

As the 3-year paper conservation fellow at the National Gallery of
Art in Washington, I am currently working on my research project on
Van Gelder Zonen papers.  I am particularly interested in the
phenomenon of "reverse foxing", the formation of white spots on
paper.

So far, I have found this damage exclusively on prints of Picasso's
"Saltimbanques" series.  But I assume it appears on other artists'
works - on Van Gelder and maybe other papers as well.

The goal of this research project will be to give a mostly visual
characterization of "reverse foxing" and hopefully some analytical
insight into the possible causes of its formation.

Has anyone encountered this damage pattern on works of art on paper
in your collections and/or conservation labs?  I would very much
appreciate hearing about your experiences and what you have seen and
heard of "reverse foxing" and/or Van Gelder Zonen papers.

Josefine Werthmann
Andrew W. Mellon Fellow
Paper Conservation
National Gallery of Art
4th and Constitution Avenue NW
Washington DC 20565
202-842-6762


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                  Conservation DistList Instance 28:17
               Distributed: Thursday, September 25, 2014
                       Message Id: cdl-28-17-016
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