Dear Sagita, Is the pigment friable, powdery? You do not say why the ceramic also requires consolidation along with the inscription pigment, or how large the fragment is but the situation you describe—a one-time opportunity to preserve the inscription-- calls out for the use of mock-ups to help you determine the best combinations of material and methods ahead of time. You might get some good suggestions from people, but the best way is to use them as a starting point to find out for yourself by careful testing.
I suggest you obtain a modern ceramic flowerpot with similar appearing characteristics and recreate lines of the inscription using the range of possible organic black pigments; carbon black, lamp black, etc. Cut or break the ceramic into a group of sherds, and test all of the options and variables you can think of. These will include application method, material, concentration, number of coats, etc. I cannot advise you on which consolidant will be best (I usually reach for B-72 in Acetone/Ethanol because it is a class-A material, I’m very familiar with it, and Americans use B-72 for everything!) but I would suggest trying a wider range of application methods. Experiment with absorption by capillary action—placing the sherd in a shallow container with consolidant touching the bottom so that the liquid is drawn up into the ceramic body. Application to the surface with a dropper is also a slow, controllable way to apply the consolidant; these are both gentle, non-contact methods. You might even combine them. Using two rounds of consolidation with the second being at a higher concentration may not be necessary—your testing should tell. I’d also be worried about full immersion, which will set up a pressure differential within the sherd—all the air bubbles rushing out could displace the pigment as the solvent softens the first consolidation. Afterwards, placing the sherd in a loosely closed bag to slow down the evaporation rate during drying will help avoid a shiny build-up on the surface. Thanks to Steve Koob for suggesting some of the above issues and techniques originally, and good luck with the consolidation. Let us know what worked for you. Best regards, Tony Tony Sigel Senior Conservator of Objects and Sculpture Straus Center for Conservation and Technical Studies 617-496-1903 FAX 495-0322 [email protected]<mailto:[email protected]> Harvard Art Museums 32 Quincy Street, Cambridge, MA 02138 www.harvardartmuseums.org ****** Unsubscribe by sending a message to [email protected] Searchable archives: http://cool.conservation-us.org/byform/mailing-lists/cdl/
