Bust

>I have a bust in the conservation lab that was fabricated in a
>method that I am not familiar with. It was probably made in the late
>1920's or sometime in the 1930's and exhibited in a historical
>museum until last month. It is hollow--the walls are from 1-2 inches
>thick composed of what appears to be a plaster or compo material
>which is severely efflorescing nearly overall the whole interior
>surface and through breaks in the exterior surfaces in some areas.
>Covering the "plaster" and making up the exterior is a thin-1/16 of
>an inch or less metal layer (like a foil) that I suspect is copper
>or copper alloy that was patinated. It has the appearance of a solid
>bronze statue.

I have a bust in the conservation lab that was fabricated in a
method that I am not familiar with. It was probably made in the late
1920's or sometime in the 1930's and exhibited in a historical
museum until last month. It is hollow--the walls are from 1-2 inches
thick composed of what appears to be a plaster or compo material
which is severely efflorescing nearly overall the whole interior
surface and through breaks in the exterior surfaces in some areas.
Covering the "plaster" and making up the exterior is a thin-1/16 of
an inch or less metal layer (like a foil) that I suspect is copper
or copper alloy that was patinated. It has the appearance of a solid
bronze statue. It has separated from the plaster in most areas.
There are numerous breaks in this layer.

I don't have particular experience treating the kind of object Peter
Sixbey is describing, but if I had to deal with such a problem I
certainly would, despite the fact that the bust Peter Sixbey has to
deal with is from the beginning of the 20th century, consult a major
book with just has been reedited and is the 1983 publication
resulting from a major study Ulrich Schiessl (now Conservation
Training Programme, Art Academy Dresden, Germany) conducted between
1978 and 1981 with the support of the Volkswagen Foundation during
his conservation education at the Stuttgart Art Academy--it is a
very rich source of technological information on the kind of
decoration techniques and their technology Peter Sixbey is
confronted with and which Schiessl, each time and where possible,
verified on the real object.

The bibliographic data of the 1st edition:

    Ulrich Schiessl
    Techniken der fassmalerei in barock und rokoko
    Werner sche verlagsgesellschaft
    Worms, 1983

Hans-Christoph von Imhoff
Conservateur-restaurateur
CR-SCR, FIIC, PA-AIC, SSCR, UKIC
Lorette 28
CH - 1700 Fribourg / Suisse
+41 26 321 14 44
fax: +41 26 321 14 40


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                  Conservation DistList Instance 13:53
                  Distributed: Monday, April 24, 2000
                       Message Id: cdl-13-53-004
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