Housing oversize parchment

We have a number of portolan charts in our collection, as well as
other large maps and manuscripts on parchment and vellum.
Currently, they're stored flat in boxes, in some cases with
acid-free tissue or other materials to provide some support.  I
would be most interested to hear from others, though, who have
similar materials in their collections.  How are you housing these
documents to protect and support them, both while in storage and
during transport to the reading room, without constricting them too
much during modest seasonal fluctuations in RH?

Thanks very much for any guidance and insight you can provide.

Mary Miller
Director of Collection Management and Preservation
University of Minnesota Libraries
31A Wilson Library
309 19th Ave. South
Minneapolis MN 55455
612-625-9176


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                  Conservation DistList Instance 29:10
                  Distributed: Thursday, July 30, 2015
                       Message Id: cdl-29-10-012
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