Glass plate negatives

We have a collection of glass plates that are tarnished and have
flaking of the emulsion layer.  Interestingly the surface of the
glass itself appears to be flaking off with the emulsion layer.  We
have never observed this kind of deterioration before and are
interested in the observations or speculations of anyone who might
have encountered this process.  We are duplicating the plates onto
polyester film base as quickly as resources permit but are still
concerned with long term storage of these images.  I have digital
images of the some of these plates which can be sent as an e-mail
attachment if anyone wants to see them.  I welcome anyone's ideas or
even speculation regarding this and appreciate any help that can be
provided.

William L. Hopkins
Coordinator, Archival Services
American Heritage Center
University of Wyoming
PO Box 3924
Laramie, WY 82071
307-766-6836
Fax: 307-766-5511


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                  Conservation DistList Instance 16:34
                 Distributed: Friday, November 22, 2002
                       Message Id: cdl-16-34-027
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