Sculpture carving medium

Sculpture Carving Medium: Polyvinyl Acetate Emulsion/ "Dead"
(hydrated) plaster, and pine sawdust.

Has any one had any experience restoring or cleaning the above
sculpture medium? According to the artist, it was commonly used as a
medium during the 1950's. When initially applied it was white in
colour, but over time has discoloured to an uneven beige/light brown
colour. There are also brown tide lines, and engrained dirt on the
horizontal surfaces. This particular sculpture has been displayed in
the foyer of a public building for over 40 years. Thanks,

Sandra Lougheed

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                  Conservation DistList Instance 11:76
                 Distributed: Wednesday, March 11, 1998
                       Message Id: cdl-11-76-015
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