Discoloration of photographs

One of our volunteers recently approached us with a problem
regarding her family photographs.  Some of the oldest (tintypes and
prints on paper) had been stored on inexpensive "magnetic:
pages--the kind with lines of some adhesive on them.  She knew this
was not great, and checked them regularly. this year she found that
red staining had developed where the photographs were in contact
with the sheets.  The stains leach through to the other side of the
cardboard sheets, and on to the back of the photographs. Sometimes
they are stronger on the side opposite that on which the photograph
was stored.  She immediately removed all the photographs, but is
concerned about them.  Has anyone heard of this sort of staining?
It does not appear to be mold, more like a chemical reaction of some
sort.  Her main concern is that it is on the back of the
photographs.  Is it likely to leach through to the front, and if so,
is there anything that can be done to stop it?

Genevieve LeMoine
Curator/Registrar
The Peary MacMillan Arctic Museum
Bowdoin College
9500 College Station
Brunswick ME 04011-8495
207-725-3304
Fax: 207-725-3499

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                  Conservation DistList Instance 10:91
                 Distributed: Wednesday, April 23, 1997
                       Message Id: cdl-10-91-004
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