In last week’s post, we discussed how Claes Oldenburg made his oversized soft sculpture Floor Cake, and we considered some of its current condition issues. This week we are conducting a more in-depth examination of the materials Oldenburg used to create the work. Material analysis will assist us in the development of a plan to treat the sculpture. Our treatment decisions may change as our understanding of Floor Cake increases through continued examination of both the object and its place in art history.
When developing a treatment plan for a work of art, it is essential to understand as much as possible about the materials the artist used. At MoMA, we keep extensive files on the artists and objects in our collection—from curatorial files containing past articles, acquisition information, and correspondence, to Conservation Department records documenting previous treatments, condition history, and technical analysis, among other materials—so that’s where we usually start. After reviewing all those sources, we undertook a thorough examination of the object. We began by photographing Floor Cake using a variety of lighting techniques to attempt to tease out as much information as possible. Under normal light conditions we observed that the chocolate drop appeared significantly more saturated than the rest of the cake. The drop has that gloss and sheen we associate with an oil-based paint. We suspected that Oldenburg was using acrylic paint as well as an oil-based paint he may have had left over from The Store. (For The Store, as we discussed in our first post, he used an alkyd resin paint or an ester modified with drying oils.)
The images below, captured under the same lighting conditions, show some of the variations in the surface appearance.
We spent some time sitting in front of the layers of cake discussing the artist’s technique and intention. Obvious condition issues, such as soiling and cracking, were observed with the naked eye, while minute features and condition issues were surveyed under the microscope with high-power magnification.
There are several other ways that we go about finding out exactly what materials an artist used to create an object. Artist questionnaires and interviews can provide valuable information regarding the techniques an artist used, requirements and conditions for displaying a particular work of art, and even the artist’s views on long-term preservation. Over the last four decades Oldenburg has made himself accessible to MoMA’s Conservation Department, appreciating how valuable it is for us to have direct contact with artists as we go about studying and treating their works. We are hoping to interview Oldenburg in the coming months to question him about his current view on the conservation of both Floor Cake and Floor Cone.
Until then, though, we have learned from Canadian collegues that during a 2001 conversation with the Art Gallery of Ontario, Oldenburg referred to Floor Burger as having been painted with Latex and Liquitex; curatorial records here at MoMA indicate that Oldenburg said the same of Floor Cake. Latex is essentially a house paint, while Liquitex is a brand name for an artist-grade paint. They are similar in that they both use an acrylic resin to bind pigments in an aqueous emulsion.
We also used technical analysis to confirm paint binders and colorants. Recently, we took samples (about the size of a tip of pin) of the Floor Cake paint layers and, along with Conservation Scientist Chris McGlinchey, analyzed the samples with Fourier Transform Infrared Spectroscopy. As suspected, FTIR confirmed that Oldenburg used two completely different types of paint for Floor Cake: an acrylic medium paint (polyvinyl acetate) for the icing and chocolate cake layers, and an oil medium paint for the chocolate drop. That explained the efflorescence or white residue seen on the drop—oil paints contain free fatty acid deposits that can migrate to the surface of works and create these effects.
Please come back next week as we share the treatment strategy we developed utilizing the information gathered to date.