Consolidating stone

The object is an elaborated block of chalky limestone, part of an
ancient building with carved geometric elements and some coloured
pigments residue.

There is a thin layer of dried, white lime, approximately 2 mm. On
most of this surface are some extended traces of red colour and, in
some places, upon the red, some small traces of gold leaves. In
other places, wherever there is not the red pigment, some black
colour is present, possibly fine coal powder.

On the carved geometric parts, small and large particles are easily
exfoliating and detaching. Often, the gold traces are falling even
with a mild breath.

Does anybody have experience consolidating such layers? The use of
consolidants such as acrylic polymers diluted in acetone and or
ethyl silicates diluted in white spirit, could offer a solution to
the problem--which ones?

Paolo Recanati
Laboratory of Conservation of Objects
Israel Museum


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                  Conservation DistList Instance 20:34
                 Distributed: Saturday, January 6, 2007
                       Message Id: cdl-20-34-012
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