Cleaning pre-Columbian ceramics

Jerry Fahey <jfahey [at] siue__edu> writes

>I'm preparing some small (3 to 7 inch) pre-Columbian ceramic figures
>for a display. Some people refer to them as "flats". I was wondering
>what would be the best way to clean them. They're in good shape with
>no repair work and fairly clean already. There is, however, some
>mud/dirt residue still on them possibly from their entombment.
>They are earthenware terra-cotta, some with clay slip decorations.

When you say there are no repairs, I assume you are not relying just
on visual inspection; if you do, don't trust your eyes, because many
of the repairs to pre-Columbian ceramics are extremely well
disguised. In any case, the often low-firing temperature of
pre-Columbian pottery makes it quite tricky to treat, and I have
seen surfaces, possibly the same as your clay slip decorations,
crumbling under un-careful brush touch.

If the remaining residues are unacceptable for exhibition purposes,
try and find someone who has had some experience with pre-Columbian
ceramic. You should not assume that cleaning methods normally used
for archaeological pottery are harmless on pre-Columbian one.

This is definitely a case where I would hesitate to recommend any
treatment without seeing the artefact, and just suggest that
whatever you do, do it very slowly, under magnification, and check
the effect on the surface carefully  and continuously.  With cotton
swabs a possible problem is that they can catch on the surface and
pull it away;  if you use water, use the swabs dump rather than wet.
Consider very careful mechanical cleaning, and more than all,
consider living with the dirt.

Smadar Gabrieli
University of Sydney


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                  Conservation DistList Instance 15:56
                Distributed: Thursday, February 14, 2002
                       Message Id: cdl-15-56-003
                                  ***