Consolidants for dry archaeological organics

We are interested in advice regarding a consolidant for extremely
brittle and desiccated organic remains.  A bronze disk that was
block lifted in Mongolia was brought back to our lab and micro
excavated over several years to reveal a number of organic remains
sitting on the surface of both sides including textile, horse hair,
and desiccated leather.  In order to preserve the extremely brittle
remains in-situ, we are considering using a non-aqueous
consolidant(s) that would add adequate strength to maintain the
physical integrity of the organics, be compatible with the bronze,
and would change the appearance of the materials minimally (although
some darkening is acceptable if adequate strength is imparted).  The
desiccated leather pieces, however, are easily removed from the disk
surface and could be consolidated and retained separately.

Extensive analysis and sampling have already been carried out, so
contamination is not a major concern.  Amongst the materials we are
considering are Aquazol (in ethanol), Butvar B-98, and (of course)
Paraloid B-72.  We would be grateful to hear about any experiences
using these or other consolidants on desiccated organic remains.

Ainslie Harrison
Kress Conservation Fellow
Museum Conservation Institute
Smithsonian Institution
4210 Silver Hill Road
Suitland, MD 20746-2863
301-238-1217


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                  Conservation DistList Instance 22:30
                Distributed: Tuesday, November 25, 2008
                       Message Id: cdl-22-30-013
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