Inpainting materials

Are there any painting conservators using animal-glue based
inpainting material to retouch paintings?  If so, is the material
commercially prepared, or do you make it yourself by mixing the
pigment into the animal glue? (This research is for the inpainting
chapter of painting conservation catalog)

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                  Conservation DistList Instance 12:89
                  Distributed: Thursday, May 20, 1999
                       Message Id: cdl-12-89-012
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