Lime painting on plaster

Catherine Reymond <atelierarte [at] span__ch> writes

>I'm looking for literature and especially practical experience for
>consolidation of (probably) lime painting on plaster. If not lime,
>then the painting is on an aqueous basis. The plaster has sucked
>the binding material with the time and the painting is now only
>powder, just like an unfixed pastel. It's even impossible to use a
>brush on it. The only possible way of consolidation would be a
>spray, I've been thinking of pastel fixative and also
>methylcellulose but I couldn't try anything by now.

Lime painting, as its name suggests, involves the use of an
inorganic medium. Aqueous painting (in wall paintings at least)
would involve the use of an organic medium, usually a glue size or
similar material. These two techniques are completely different. The
nature of the deterioration of the paint layer is completely
different as are the methodology and ethics of treatment. The
identification of original materials and painting techniques is an
essential prerequisite to any responsible conservation treatment.
There are certainly books on the conservation of wall paintings
which address these issues (L Mora, P Mora and P Phillipot,
Conservation of Wall Paintings, London 1984 is a good start).
However, the consolidation of pigment layers which have suffered a
serious loss of cohesion is an area where there is immense amount of
research and experience and it would be far better to consult a
qualified and experienced wall paintings conservator. (You might
want to check <URL:http://palimpsest.stanford.edu/misc/people> for
local contacts)

As far as the use of a commercial methylcellulose spray is
concerned, irrespective of its unknown working properties,
consolidation effect and long term stability there would be a
serious question as to how it would be effected by the microclimate
in the vicinity of the painting, and to the possibility of
encouraging micro-biological attack.

Tobit Curteis
Tobit Curteis Associates
36 Abbey Road
Cambridge CB5 8HQ
UK
+44 1223 501958
Fax: +44 1223 304190


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                  Conservation DistList Instance 15:35
                 Distributed: Monday, October 29, 2001
                       Message Id: cdl-15-35-005
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