Mold on stone--corrigendum

I submitted a response to the above query which was edited
incorrectly and published. I said soluene with an s, and I meant
soluene with an s, not toluene. It is the name of a proprietary
solvent, so really it should be Soluene, with a capital S. It is a
mixture of toluene, dimethyl dialkyl quaternary ammonium hydroxide
and methanol.

    **** Moderator's comments: The error was entirely mine. Not
    having heard of Soluene, I had checked the AATA abstract for the
    Rodrigues and Valero paper, which mentions refers to the mixture
    described and jumped to the conclusion that "soluene" was a
    simple typo. To avoid further propagating the error, I will
    quietly correct the typo in the DistList archives. My apologies.
    The last two paragraphs should have read:

But stopping it only succeeded in altering the color of the staining
from red to brown. Nothing we tested was successful in removing the
staining. I did some research into it, but have not had the
opportunity to do any further testing. My research turned up a few
articles, one of which

    J. Delgado Rodrigues and Jesus Valero.
    "A brief note on the elimination of dark stains of biological
    origin", Studies in Conservation (2003) 48 pp 17-22

described success with the use of poultices with toluene. This
solvent appeared from the MSDS to be quite toxic to all living
things and the environment, and therefore labor intensive in terms
of protection, containment, disposal, etc. It is also expensive. The
few other methods reported to be successful were multiple step
processes that did not seem readily applicable to a site
application. If anyone knows of a material or method that is simple,
practical, and less toxic (not to mention less costly) that is
effective for this purpose, it would be a great contribution.

Robin Gerstad
Conservator
Conservation Solutions, Inc.
503 C Street, NE
Washington, DC 20002
202-544-3257
Fax: 202-544-3229


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                  Conservation DistList Instance 19:26
                Distributed: Saturday, November 19, 2005
                       Message Id: cdl-19-26-005
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