Steamer trunk

I just wanted to follow-up on some of the excellent observations
posted by Barbara Appelbaum.  Such trunks are complex objects made
from a variety of materials all of which interact differently to
environmental conditions as well as to each other (if in intimate
contact).

Often the copper-alloy tacks and handles will exhibit a waxy
green/white corrosion phenomenon known as organometallic corrosion
which is initiated by the fatty acids contained within
leathers--both copper stearate and copper oleates are the result. It
is also common to find damage to both metal and surrounding
leather/wood due to the use of polishes on the copper-alloy
hardware.  Polish residues left in-situ can often be the locii for
all sorts of ugly corrosion and it will seriously affect the
appearance and condition of surrounding hydroscopic organic
materials.

It is always best to remove materials for treatment if practical.
However, there are some ethical issues involved here.  Hardware
which appears to have never been removed should be left and treated
in-situ (often masking around the hardware with mylar will protect
the surrounding materials). You also need to think through the whole
preservation/conservation process before doing anything.  What is
the purpose of intervention?  What are the core preservation
objectives?  What are the aesthetic issues?  What kind of time and
resource limitations are present? As Barbara aptly pointed
out--isn't it incongruous to see highly polished brasses on worn and
oxidized wood/leather?  you need to be extremely conscious of what
the real problems are and how they can be corrected in a minimally
intrusive way.

David Harvey
Associate conservator,
Metals & Arms
The Colonial Williamsburg Foundation
P.O. Box 1776
Williamsburg VA 23187-1776
757-220-7039

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                  Conservation DistList Instance 11:44
                 Distributed: Friday, November 14, 1997
                       Message Id: cdl-11-44-004
                                  ***