Soot on wall painting

Re: "Chemical" Sponges

About 15 years ago there was interest among ethnographic
conservators in finding a conservation-quality material to remove
surface dirt from rough-surfaced traditionally-tanned skin clothing.
(During original use these items were usually cleaned by abrasion
with sandstone or a chalky stone, much as we once cleaned "white
buck" shoes.)

Cornmeal was often used by restorers, but we were concerned about
possible pest problems from residues, and looked at a range of
erasers, powdered erasers, "chemical sponges" and so forth.

I believe that some good work was done on this at CCI but I do not
remember the specifics, and hope that others can fill in.

At any rate, I do seem to recall that the eraser crumbs (which
seemed promisingly effective) left microscopic particles of rubber
embedded in the surface fibers in spite of careful vacuuming and
brushing.  We were concerned about the eventual effects of sulphur
liberated by these vulcanized particles.

I don't know if this is relevant in the case of paintings or paper,
but perhaps someone could provide more precise information.

Lisa Mibach

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                  Conservation DistList Instance 12:48
                 Distributed: Monday, November 30, 1998
                       Message Id: cdl-12-48-007
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