Caring for the Museum's Pastels

John Griswold, Conservator
April 9, 2020

The Norton Simon Museum’s beloved pastels by Edgar Degas, Henri de Toulouse-Lautrec and Louis Anquetin are some of the most delicate and vulnerable artworks in the collection. In order to ensure their preservation, and to maximize the amount of time these light- and humidity-sensitive works can spend on display, we have recently taken two major steps. We are converting our galleries to LED lighting, and we have started an initiative called the Pastel Rehousing Project.

One of the first galleries to benefit from the museum-wide lighting upgrade was the so-called “pastel gallery” in the 19th-century wing, home also to Degas’s Little Dancer, Aged Fourteen, displayed there because of the light sensitivity of the sculpture’s tulle skirt. These aren’t your average hardware store LED bulbs: this is a state-of-the-art system developed specifically for museums, providing the most stable, consistent and controllable output of light possible. Remarkably, these new lights enable color and detail to be perceived clearly by the average human eye at lower light levels than the previous halogen spotlights allowed. This means that about 20 percent less light is falling on our most sensitive artworks, even while visitors can discern their visual qualities better than before.

The Pastel Rehousing Project began in 2019, when our art handling staff and I received specialized training from Michelle Sullivan, Associate Conservator in the Department of Paper Conservation at the J. Paul Getty Museum. The goal of the project is to replace outdated matting and framing components, and to protect the artwork within a sealed, environmentally stable package. The package incorporates antistatic glazing, a new window mat, sheets of humidity-buffering material, and custom-fitted mat board enclosures that support the artwork with even, gentle pressure at the edges. The newly encapsulated artwork fits right back into its existing frame.

The most gratifying aspect of the project has been seeing the pastels unframed for the first time in decades, affording an opportunity to learn more about the artists’ working processes. The old, linen-covered, gilt-edged frame liners, most dating to the 1970s, tend to conceal illuminating details. We found that the artworks are often still attached to stiff cardboard backings, pasted or taped in place by the artist before beginning the work. This rigid backing enabled the artist to work more freely and energetically, as it supported even quite vigorous handling of the pastel crayon. It also kept the paper flat as liquid mediums such as gouache and peinture à l’essence—tube paints drained of their oil and thinned with turpentine—were worked into the surface. Degas took particular advantage of the flat backing board as he added strips of paper to enlarge his composition.

We also discovered that the edges of these complex objects are extremely fragile. After carefully stabilizing the paper, glue, tape and cardboard of the original assemblies, the edges of the artwork were captured within folding hinges of mat board, cushioned with slings of strong, flexible Japanese tissue. This system allowed the heavy original assemblies to be evenly supported inside the sealed enclosures, while making their details more visible within the frame.

Each artwork requires about a month or two for the design and fabrication of the custom-sealed package, depending on its complexity. To date we have completed almost a dozen Degas masterpieces, which will be rotated into the pastel gallery in the year ahead.

John Griswold is the Conservator of the Norton Simon Museum, where he leads efforts to preserve and care for the Simon collections.