Metal printing plates

Dartmouth College's Special Collections Library has the original
printing plates of Rudolph the Red-nosed Reindeer, which have some
preservation issues.  The plates, dating from 1939, were stored at
the author's house for many years in a wooden packing crate.  Little
is known about the specific conditions of the storage environment,
except that they were most likely in the attic.  The Special
Collections Library received the plates and crate recently and would
like to use them for a holiday-themed display this year.

The plates, which could be zinc (but I'm not positive) are covered
by a white substance, which originally was thought to be mold.  I
don't think it is mold, but rather some oxidation on the surface.  I
am not a metals conservator, but was asked to experiment with one of
the less interesting plates.  I tried washing in DI water and
lightly scrubbing the surface.  The white substance seemed to
disappear while wet but reappeared just as much as before when it
dried.

I would be interested in any methods we might be able to remove this
(assuming it is oxidation) which could be accomplished by a book and
paper conservator.  Or, if this isn't going to be an easy job, any
leads on where we might be able to have these cleaned up.  Dartmouth
College is located in New Hampshire, USA.

    **** Moderator's comments:   The Foundation of the American
    Institute for Conservation (FAIC) has a service called the AIC
    Guide to Conservation Services, which will help you find a
    conservator in a particular specialty and geographic area.

        American Institute for Conservation
        1717 K Street, NW, Suite 200
        Washington, DC 20006
        202-452-9545
        Fax: 202-452-9328
        info [at] aic-faic__org
        <URL:http://aic.stanford.edu/>

In case it helps, here a few other specifics: There are
approximately 200 plates, ranging from roughly  6 x 9 inches to
about 10 x 14 inches.  The printing process was spot color, not
color separations (and the results have been described as "crude and
simple printing," although I haven't seen the finished book).  The
box they were stored in shows signs of insect damage and it is not
known if the box and/or plates were exposed to direct water or
sunlight.  It is not known if there was any packing material in the
box when the plates were stored in it or what it might have been.
And in case you are wondering, Dartmouth acquired these plates
because the author of Rudolph, Robert May, was an alum of the
college.

Eric Alstrom
Collections Conservator
Dartmouth College
Hanover, NH
603-646-1452


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                  Conservation DistList Instance 17:31
                Distributed: Monday, September 29, 2003
                       Message Id: cdl-17-31-020
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