Grease stains on glazed earthenware pot

Does anyone have experience removing grease stains from a glazed
earthenware pot that has (I think) been used as a dripping pot? The
entire body of the vessel is stained dark grey/ brown, and the
finely cracked glaze oozes white, yellow and red grease on soaking
in hot water and detergent. I have tried various poultices and
solvents, which have done little to lighten the staining.

Sara Freeman
Student of Cultural Heritage Conservation
University of Canberra
Australia


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                  Conservation DistList Instance 24:27
                Distributed: Tuesday, November 30, 2010
                       Message Id: cdl-24-27-020
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