Corrosion of brass mats in cased photographs

I am posting the following inquiry for someone who is not a list
member. As this topic is of interest to me as well, I would
appreciate responses posted to the list rather than just to Ms.
Longford. I will be forwarding to Ms. Longford all responses posted
to the list. (This inquiry also posted to the PhotoHst list.)

    I am an objects conservator at the Missouri Historical Society and
    am carrying out some preliminary studies on the corrosion of brass
    mats (of cased images.) I was wondering if you could perhaps
    assist me in finding out more information or about brass mats;
    their manufacture and general history.

    What is the general interest about brass mats and their
    corrosion? Do you know of anyone who cleans and "touches" brass
    mats up for presentation? I am especially interested in any
    information about their manufacture which would assist in the
    development of conservation treatment recommendations for brass
    mats in the near future.

    Thanks for your time, and I would appreciate any potential
    contacts, questions, and corrosion curiosity out there in the
    daguerrean community.

    Nicola Longford, Objects Conservator
    njmlt [at] aol__com
    Missouri Historical Society
    P.O. Box 11940
    St. Louis, MO 63114-0040
    314-746-4543
    Fax: 314-745-4548

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                  Conservation DistList Instance 10:33
                Distributed: Wednesday, October 2, 1996
                       Message Id: cdl-10-33-006
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