Algal growth on plaster

Frank Briscoe <frankbris [at] earthlink__net> writes

>I'm working on a couple of masonry buildings on the Rio Grande in
>South Texas. One has been without a roof for several years and has
>developed algal growth on the interior surface of the south wall. I
>plan to consolidate/readhere the plaster at this and other areas
>using M. Weaver's recipe, and wonder if there are suggestions about
>how to deal with the algae where it has developed between the
>plaster and the sandstone substrate.

The green- blue green chlorophyl is alcohol soluble. It may be
possible to poultice out the stain using ethyl alcohol. The alcohol
will also kill the cells.


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                  Conservation DistList Instance 17:44
                Distributed: Thursday, December 4, 2003
                       Message Id: cdl-17-44-003
                                  ***