Copper plates

Recently we had some water ingress in our copper plate store where
some of the copper plates were in contact with water.  I would like
to ask colleagues on this list for information/advice on the storage
of copper plates and what type of damage can occur when copper
plates are exposed to water.  The copper plates have a coating of
wax and currently stored upright in zinc shelving.  My main
questions are:

    1.  What is the optimum storage conditions for copper plates?
    2.  What effect in terms of chemical reaction can be expected if
        copper plates are subjected to water/moisture?
    3.  Why store copper plates in zinc shelving?
    4.  Why have a wax coating?

The answers to the above questions may be obvious to some colleagues
but I would appreciate feedback on this.

Rab Jackson
National Library of Scotland


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                  Conservation DistList Instance 14:26
                Distributed: Wednesday, November 8, 2000
                       Message Id: cdl-14-26-019
                                  ***