Stain on paper

We are currently conserving a series of 16th  and 17th century
manuscript volumes on paper. The most recent volume to be taken down
has a green stain concentrated down the spine and particularly
towards the bottom of the volume. The stain runs through the book
but is not uniform in its extent or intensity. It does not have a
definite  edge but rather fades away to nothing. When the volume was
initially taken down there was a distinct solvent like smell
associated with the stain though over the weekend this seems to have
gone.

I have consulted the university's chemistry department but they were
unable to suggest what it might be. These volumes have not
previously been conserved in any way so the only treatment that they
might have received would have been Thymol fumigation or leather
dressing. We have ruled both of these possibilities out. I have
checked the other volumes on the shelf and only the next one along
seems to have any staining and in that volume it is much less
extensive.

We suspect that the stain may predate the 1820's when we think these
books were bound up, probably for the first time. We base this on
the fact that on one section some of the folios have been bound in
upside down and the stain is also reversed.

Can anyone suggest what this stain might be? Has anyone come across
anything similar?

Catherine Bonnett             Conservation
Palace Green Library
Durham DH1 3RN
+44 191-374-3201

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                  Conservation DistList Instance 11:23
                Distributed: Tuesday, September 9, 1997
                       Message Id: cdl-11-23-011
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