Conservation of Pieta,
Wood Relief by Malvina Hoffman

Bernacki & Associates, Inc.

Malvina Cornell Hoffman (1885-1966), an American sculptor who studied with Auguste
Rodin, is perhaps best known for her monumental bronze series, The Races of
Mankind, commissioned in 1930 by Chicago's Field Museum of Natural History.
In 1985, The Cedar Rapids Museum of Art accepted Hoffman’s Pieta (1960) as a gift
along with other notable pieces. The Pieta, carved on a walnut panel, (54 ¼” H x 42
¼” W x 3” D) had never been exhibited at CRMA, but in 2008 was exposed to flood
waters, and rediscovered during the conservation treatment.

In the late summer of 2008 the Midwestern United States endured some of the worst
flooding in recent history. Several area homes, institutions and museums had to be
evacuated as the rivers rose. The Cedar Rapids Museum of Art was one of many
institutions whose collection was in danger of the rising waters. Although much of the
collections contents were removed unharmed, some pieces suffered exposure to high
levels of humidity, moisture and other environmental conditions related to the severe
flooding. With the help of trained art handlers and conservators from Conservation and
Design International from Chicago, Illinois, all of the items in danger and damaged
were removed from the pending threat and brought to a secure location for proper
cleaning, treatment and storage. Of the many items treated and cleaned, one provided
us with an example of how high levels of humidity and exposure to moisture can affect
the stability of a carved composition in a solid wood panel.

Malvina Hoffman’s Pieta was exposed to rising levels of relative humidity (RH),
temperature change and standing water. The panel is constructed out of three
separate members of solid walnut, glued together and joined in the back by two
mortises and tenons. Wax had been applied to the surface and evidence of the
artist’s original penciled layout was still visible along Mary’s hand and Jesus’ face.
Due to the increased RH and changing temperature, several sections of the oak end
grain began to expand causing the edges of the panel, at both the top and bottom,
to develop expansion cracks which stretched inward along the grain towards the
intricately carved center. The water stained areas on the surface generated a white
cloudy haze where wax had built up in the relief carving. The sections of the panel
had sustained abrasions and dents along the sides, sections of the wood had
become stained by oils and residues, and the bottom edge showed evidence of minor
mold development. All of these issues were noted in a condition report and a
treatment was designed to correct the defects and conserve the panel.

The first step in the proposed treatment was to stabilize the panel and allow the
moisture in the wood to slowly level off. The composition remained in a climate
controlled room with an adequate RH level for four weeks. The expansion cracks were
monitored and measured periodically to ensure that further separation ceased.
Once the cracks had stabilized, filler was needed to compensate for the open gaps.
Shims of balsa wood were cut and sized to fit in each of the individual areas.
The balsa wood shims were then coated on one side with a PVA (plasticized polyvinyl
acetate) and pressed into place and trimmed flush to the panel edges.

The next step in the conservation process was to remove the existing wax, stains
and oily residue from the surface. Solutions based with alcohol, ether & naphtha were
applied to the surface and then gently washed over. The original pencil sketching was
carefully avoided during these processes to maintain the original composition.
A PH neutralizing detergent and a final rinse wash were the last steps in cleaning.
With the surface clean and free of invasive matter, water based pigments were applied
to the balsa wood in-fills to match the existing oak panel. The abrasions and dents
were also toned to match the surrounding areas to provide a uniformed aesthetic
surface. The last treatment related to surface conservation was to apply a protective
Paraffin wax layer over the panel. This wax was melted to forty-eight degrees Celsius
and applied by brush onto the panel. Once the wax cooled it was hand rubbed with a
cotton cloth to produce an even and low luster finish. This wax application will provide
additional protection to the composition from dust and or other residues from
penetrating the surface.

The final step involved in conserving the Hoffman panel was to fabricate a steel frame
that would control the movement of the wood and allow for adequate and safe
exhibition upon its return to the Cedar Rapids Museum of Art. A frame was fabricated
out of mild-steel and welded together to fit the perimeter of the panel and remained
recessed from the front face edges. The recessed profile was a small detail but
important as not to distract the viewer from the composition. The frame was painted
a flat black color and rubber cushions were installed where the panel rests against the
frame. The frame was fastened to the back side of the panel using the existing holes
from previous installations. The treatment was complete at this stage.