Egyptian furniture

I have been examining a chair in the Brooklyn Museum of Art
collection from 18th dynasty Egypt. One interesting discovery has
been through X-ray examination. Apparently a material, more radio
opaque than wood, was used to fill voids throughout the
construction. This material is found in the mortise chambers of the
joinery, also between laminates of the seat back from which a sample
has been taken. It appears that this material has both organic and
inorganic components. Under magnification an amber colored
transparent component has been noted which we suspect is a natural
resin. A vigorous gas evolution has also been observed upon
treatment with nitric acid that suggests a carbonate component.
Formation of crystals similar to those of sulphate was observed upon
drying.

I am trying to determine whether this material is original to  the
chair or a later restoration.The sample will be sent away for
analysis to make sure the components are consistent with those that
were available in Northern Africa during the 18th dynasty (1580-1314
b.c.). If there is anyone who has encountered  a similar material on
Egyptian wooden artifacts, or is familiar with Egyptian joinery
techniques, please contact me.  Thanks,

Andrew Fearon

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                  Conservation DistList Instance 12:56
                 Distributed: Tuesday, January 5, 1999
                       Message Id: cdl-12-56-019
                                  ***