Discoloration on paper

A client has given me a framed object on paper. The paper appears to
be old and has darkened considerably. It is adhered to handmade
paper and was in contact with the glass as there was no spacer
present. The object consists of a hand-painted illustration, a blue
stamped seal of the Government of India, and a postage stamp which
is adhered to it. There are curious white spots all over the paper
which have the shape of a certain type of foxing. These are not on
the surface but have stained the paper. Could it be reverse foxing?
If so, has the cause and therefore the solution of reverse/negative
foxing been determined yet? To give you a bit more information, the
painting was procured in New Delhi (dry climate) and then brought to
Mumbai very humid climate) and was not displayed on the wall, but
stored, till it was brought out and found to have been affected by
this phenomenon. Incidentally, the client has 3 more similar
paintings bought at the same time with the same problem.

Saloni Ghuwalewala
Conservator of Paper Objects
Mumbai, India


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                  Conservation DistList Instance 15:52
                Distributed: Thursday, January 24, 2002
                       Message Id: cdl-15-52-018
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