Removing shellac from plaster of Paris

Is it possible to remove old discoloured shellac from a work in
plaster of Paris and recoat it to look as the artist intended? Any
help very gratefully received

Kate Roberts
Museum of New Zealand/Te Papa Tongarewa

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                  Conservation DistList Instance 9:14
                   Distributed: Friday, July 28, 1995
                        Message Id: cdl-9-14-009
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