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Photo of Shelley Sturman Returned to Glory -- Shelley Sturman

National Gallery of Art conservator Shelley Sturman helped restore an important part of American art and history. The Shaw Memorial was originally created in 1897 by Augustus Saint-Gaudens and is America's first monument to African-America soldiers. Sturman took Frontiers viewers behind the scenes as she answered questions about conservation and restoration at the National Gallery.

QWhat happens when you and you staff feel that a piece of artwork needs to be restored and the artist who is still alive is strongly against the restoration?

AYou ask how we would handle a situation where the conservator and artist disagree about the need for treatment. Needless to say, we try not to get into that kind of disagreement, but rather try to use those situations as opportunities to set up a dialogue with an artist and point out what conditions may be present that could cause potential damage for the work of art. It is also very important to learn how the artist feels about changes in the piece from the way it may have looked originally. We talk back and forth sharing ideas and offering suggestions, some more helpful than others. Usually an artist is very pleased that we are concerned about the future preservation of his or her art and we find that they request and trust our recommendations.

I'll give you a simple example where it was critical to know the artists' intent about a sculpture and how differently two artists feel about a similar condition. During an exhibition of contemporary art, one sculpture made of highly polished chrome had fingerprints along the edges. When the artist saw the fingerprints he asked that we keep it clean at all times. Apparently he had used several different contractors and worked very hard to achieve the brilliant polish on the piece and he wanted it to remain looking just the way it did when it left his studio. So our staff had to painstakingly clean the sculpture every day. In that same exhibition, another sculpture made of copper-plated aluminum by a different artist, arrived at the museum with dark fingerprints etched into the surface, that were actually corroding the copper. When I pointed this out to the artist and asked him if he would like us to try and remove them and conserve the surface, he said he didn't care because the sculptures were meant to be played with and the fingerprints were just part of the history of the piece. He then removed the "Do Not Touch" sign that had been placed next to his sculpture. You see, there are no easy answers!

QI got the impression that St. Gaudens' vision for the sculpture was somehow realized more truly with this restoration. I'm very curious to know if and how he was disappointed with what his original effort turned out to be.

AWe tried very hard to recreate Augustus Saint-Gaudens' final vision of the Shaw Memorial for this installation at the National Gallery of Art. As we described during the Scientific American Frontiers program, a major part of the challenge of this project was determining how the artist actually finished the surface. Unfortunately Saint-Gaudens died in 1907 and we could not consult him, nor has anyone been able to find any color images of the piece from the beginning of this century. By taking many small samples of the paint layers from all over the monument and examining them under the microscope and identifying the materials used, we were able to learn that originally the artist gave his plaster Shaw Memorial a surface that looked more like a polished and patinated bronze and it was exhibited that way in Paris for the Exposition Universelle in 1900 and again in Buffalo, New York for the Pan American Exposition in 1901. But in 1905, shortly before Saint Gaudens died, it appears that the Memorial was gilded for the Inaugural Exhibition of the Buffalo Fine Arts Academy. After that exhibition opened, and under Saint-Gaudens direction, the bright gold leaf was probably toned. We believe the surface must have looked like the one we've created now.

QThis sculpture seems to have had many other attempts at restoration over the years, yet they did not seem to preserve the sculpture appropriately. Now that contemporary restorers have modern technology in their toolbox, are you confident that the restorations being done today will be appropriate and long-lasting?

AYour question about the longevity of the materials conservators use to treat works of art is very important, and one that is always on a conservator's mind. In fact, it is addressed in our professional Code of Ethics and Guidelines for Practice. Conservators realize that a treatment performed this year is just one part of the ongoing care of a work of art and that there will be others in the future entrusted with its preservation. With that understanding, the conservator only undertakes treatment that is appropriate for the art, taking into account an object's condition, history, and aesthetic characteristics. Sometimes we use the approach of "minimal intervention" meaning a treatment strategy of doing the least possible to the object that could in any way compromise the valuable aspects of the art or eventually result in more rapid deterioration. Sometimes that means that no treatment is recommended.

A conservation professional is responsible for choosing materials and methods that are consistent with currently accepted practice. The advantages of the materials and methods chosen must be balanced against their potential adverse effects on future examination, scientific investigation, treatment, and function. We work closely with other scientists to obtain the best possible materials, often ones that have been developed for industrial purposes. Before using a product, we test it on non-artworks for appearance and handling. We also perform "artificial aging" tests on materials in special chambers using heat, light, and moisture to determine how a product will change over time - will it darken, shrink, crack, lose its adhesive properties, or become impossible to remove? Our first choices are materials that have stood the test of time and have been used favorably for many centuries or those that have been artificially aged to the equivalent of 100 natural years without changing. In addition, some conservation scientists are producing new materials specifically for works of art that have good aging qualities and do not have negative reactions with the materials of which the art object is made. Though not always possible, the concept of "reversibility" guides most conservation treatments; that is, materials used for a treatment should be removable without harm to the original materials.

QIt seems like you have an interesting and challenging job. I'm curious to know what is your favorite project you've ever worked on and why?

AYou are right -- Art Conservation is an exciting and rewarding profession and I believe that it truly provides a unique blend of art and science, or as Alan Alda titled this program, conservation certainly is about the "Art of Science." No two days are alike for me; I am continually challenged to be both creative and scientific in my approach to asking questions, researching a problem, or performing "hands-on" treatment to a work of art. It is impossible to say that one particular project was my favorite. I would certainly include the Shaw Memorial among my favorite and most challenging projects for a number of reasons. It involved collaboration with many colleagues from all over the country each with a different expertise. We asked a lot of difficult questions and then had to figure out ways to answer them. I was personally involved in practically every aspect of the project, an undertaking that took almost two years to complete from the time of our initial negotiations with the National Park Service. When you are that close to something for so long, it becomes very special to you. And certainly not least important, the overwhelming positive response from all the visitors able to view the sculpture "returned to glory" in the museum or those like yourself, able to watch the work unfold on television or on the internet, make all the effort and energy well worthwhile and cause me to count the Shaw Memorial as one of my favorites.

QWhat is gold leaf composed of and how is it applied. Can a regular person like me buy some, and if so, where would I get it?

AGold leaf is real gold that has been rolled under great pressure and repeatedly beaten with hammers, until it has been reduced to a thickness of about 1/200,000 to 1/300,000 of an inch. That is much, much finer than the aluminum foil you probably have in the kitchen. It takes about 2000 sheets of the 3 1/2-inch squares of gold leaf to weigh one ounce. Gold leaf is generally sold in books of 25 sheets of leaf and should be available in well-stocked art supply stores. You can purchase it in varying degrees of purity such as 23 karat gold that has a deep, rich yellow color of pure gold; 18 karat that has a lemony-gold color; and 16 karat that is paler because it has more silver. Price will vary with quality of the gold and thickness of the leaf. Other metals such as bronze and brass are also made into leaf, but they usually are not as thin as actual gold. The aging properties and color of the non-gold leaves also vary.

Gold leaf is one of the flimsiest and most fragile of materials, and it is extremely difficult to handle. If you are able to pick up a single leaf and hold it up to the light, even though it is opaque and metallic, you will be able to see light through it; but if you breathe sharply on it, the gold leaf will disintegrate into pieces. Traditional techniques developed over the centuries for handling and applying the precious leaves are still practiced today. Gold leaf is placed on a leather gilder's cushion shielded on three sides from air currents, flattened by gently blowing on it to remove the wrinkles, cut using a gilder's knife, and lifted with a gilder's tip, a type of flat brush that is rubbed along the gilder's hair or face to make it slightly oily in order to help pick-up the thin sheet.

There are two ways of gilding with gold or other leaf: 1) water gilding and 2) mordant or oil gilding. Mordant gilding is much simpler and easier for the beginner. An oil or mordant size is applied to a nonabsorbent surface and allowed to partially dry. Then the leaves are applied making sure to overlap all the edges. Water gilding requires more skill and careful preparation of a gesso surface. The gilder wets an area of the gesso, sometimes adding a small amount of gelatin or glue to the water. When the leaf is touched to the wet gesso it is attracted to the surface almost like a magnet. If you do everything right, the leaf will lie flat on the surface. Finally, a bright finish is obtained by rubbing the gilded surface with an agate burnisher once it is dry.

Good luck in your search for gold leaf and please get more complete instructions on how to handle and lay the leaf before you attempt gilding on your own.

QIs the Saint-Gaudens sculpture the most difficult restoration you've been involved with? If so, why? If not, what was your most challenging project?

AIt is not easy or even possible to choose one project as the most difficult. Certainly, the Shaw Memorial was an extremely complicated project that involved coordination of many specialists -- it was even worrisome at times, for example when the monument was being dismantled section by section in New Hampshire. We had to anticipate all kinds of possibilities of when or how something could go wrong and then figure out how to avoid having anything like that happen. Also, at the beginning of the project there were differing opinions about what the sculpture may have looked like during Saint-Gaudens' lifetime and we had to do quite a bit of research both through analytical means and art historical ones, in order to reach a consensus about how the conservation should proceed. Look at my answer to the question above about a favorite project -- I couldn't name any one piece, but I can assure you that the more challenging and difficult the work is, the more satisfied you feel once it is successfully completed.


Scientific American Frontiers
Fall 1990 to Spring 2000
Sponsored by GTE Corporation,
now a part of Verizon Communications Inc.