Shrapnel shell

I am a conservation student currently working on archaeological
material mostly from late 19th to early 20th centuries.  Amongst the
material are two dud shrapnel shells that are causing trouble.  The
shells are composite objects that consist of an iron or steel shell
wall filled with lead bullets held in position with resin.  A copper
metal band surrounds the shell wall, and there are some other copper
metal parts here and there around the object.  Currently the iron
parts of the objects show signs of active corrosion, and the objects
require some sort of stabilization.

The problem is that it is not possible to remove the copper metal
without causing severe damage to the object, and all effective iron
stabilization methods that I know of are unsuitable for copper
metals.  The lead balls inside the shells can be removed if need be.
I have been trying to find a good source of composite object
stabilization, but so far I have come up with nothing particularly
useful.

I would be very grateful if anyone could share their experience in
iron-copper composites stabilization.  If someone knows a good
source about the subject, that would be very helpful too.


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                  Conservation DistList Instance 28:10
                  Distributed: Sunday, August 10, 2014
                       Message Id: cdl-28-10-010
                                  ***