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The Sieve of Eratosthenes

June 16, 2014

Mark Di Suvero’s The Sieve of Eratosthenes was added to the university’s outdoor art collection in 2000 by Daniel Shapiro and Agnes Gund. It was originally sited on the north side of the Cantor Arts Center and was recently moved near the intersection of Escondido and Galvez Mall by Meyer Library.

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The new location puts The Sieve of Eratosthenes in greater student traffic. The sculpture invites viewers to experience its form from all sides and even underneath. This does not, however, condone the following:


hammock No hammocks on the sculpture!


In spite of the sculpture’s powerful forms and seeming imperviousness of its I-beams, the sculpture is still susceptible to degradation. In addition to looking fantastic, the paint and primer layers protect the underlying steel from corrosion. When vandalism occurs to the paint surface, the steel is exposed to the environment and leads to rust.

The outdoor sculpture team works hard all year long to care for Stanford’s sculptures, so do your part! If you are trying to get your work done or “play” around the sculpture, try also to take a few minutes to contemplate the beauty of its forms and how this reflects Di Suvero’s perception of reality. Think about the enormity of the feat that brought such a massive object into existence. Let this object inspire whatever non-vandalizing activity you are engaged in!



Please Don’t Step on the Art

April 11, 2014

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Auguste Rodin’s The Three Shades (created 1881-1886, cast 1979-80) is currently on view at in the Rodin Sculpture Garden just off Lomita Drive. The sculpture’s location, pose, scale, and low platform make it particularly vulnerable to visitor damage. Recently, the patina on the base of The Three Shades was extremely abraded. Note the bright golden color of the metal showing through!

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(above) The dark brown patina was worn away by visitors standing on the bronze base, probably due to a tempting photo opp. 


Wax is an important protective layer for bronze, as it slows down corrosion and serves as a barrier from abrasion, graffiti, and other undesirable occurrences. The Stanford outdoor sculpture conservator and maintenance crew spend much of their time maintaining the coatings on the University’s collection. The wax coating on the base of The Three Shades was painstakingly rebuilt over several days.


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(above) Several layers of a pigmented microcrystalline wax were added to the base and buffed afterwards. 

So please, don’t step on the art!

Stanford News: New maps showcase public art treasures on campus

November 25, 2013

Stanford News: New maps showcase public art treasures on campus





Stanford News



Direct Link to: Stanford Arts Map

Outdoor Painted Sculpture (gettyconservation)

October 30, 2013

Outdoor Painted Sculpture (gettyconservation)

That’s a Wrap: Protecting the “Burghers” From Construction

September 17, 2013

That’s a Wrap: Protecting the Burghers From Construction 2013-08-18 16.35.19

author, Lauren Sweet

This past month The Burghers of Calais have been kept under wraps. No, they haven’t been shrouded in secrecy, they’ve been swaddled in blankets. The Burghers of Calais, one of Auguste Rodin’s most famous collection of statues and among the premier pieces in the Stanford collection, have been in preventative protection during a nearby drainage-modification project (the old system was causing pooling).

The Outdoor Sculpture Conservation Crew first washed the statues using a mild detergent called Orvus, then rinsed and dried the bronzes with lint-free rags. The state of the protective wax coating was assessed, and the six bronze men were wrapped in heavy duty blankets (more about this process here…). Once the construction was complete, the statues were unwrapped, safe, sound, and ready to pose with their many visitors.



Hot Waxing The Gates of Hell

August 27, 2013
Maneuvering the boom into position

Maneuvering the boom into position

Authors: Lauren Sweet, Bryce Cronkite-Ratcliff, Elizabeth Saetta

Rodin’s The Gates of Hell is one of the crowning jewels of Stanford’s sculpture collection. A monumental work of this scale requires a significant conservation effort. As with all sculptures in the outdoor sculpture collection, The Gates is cared for by the conservation crew, and its condition is constantly monitored. All bronze sculptures receive an annual treatment of washing, waxing, buffing, and any other additional conservation treatment necessary, including touch-ups. This conservation work preserves the sculpture in perpetuity and heightens visitors’ experiences of it.


The Treatment:  August 5th through 9th 2013

Preventative conservation treatment of The Gates of Hell is a weeklong project. The work began early on a Monday morning with a thorough washing of The Gates. The conservation crew faced many challenges: first, how to reach and wash the upper reaches of a massive sculpture nearly 20 feet tall. A 45-foot electric boom lift with an articulated arm was the answer, but this posed its own challenges, including how to maneuver the lift into a garden full of other priceless Rodin works, and how to position it in relation to the large, broad, raised pedestal that The Gates sits upon so that the arm of the lift could extend to reach the entirety of the sculpture. In areas where the lift arm could not reach, a large ladder was used.

washing gates

Washing the “Gates”: Stanford Student and Outdoor Sculpture Coordinator and Conservator Elizabeth Saetta wash the gates (left) with water and soft brushes (center) and dry the surface with soft towels (right)

Once these logistics were smoothed out, the cleaning could begin. An entire day was dedicated to washing The Gates. Every crevice of the sculpture had to be rinsed, washed with soft nylon brushes and a gentle detergent known as Orvus, rinsed again, and then dried. All of these steps are crucial. The first rinse helps to remove large debris or dirt accumulations on the sculpture. Interesting things were found at this stage, including several small rocks high up in the top pockets of the sculpture and a headband that must have been slung onto the roof of the piece. Soap and soft scrub brushes do what one would expect, assisting in the removal of the tougher grime, including things like bird droppings. Another unexpected discovery during the treatment was four individual wasp nests, nestled in among the twisting figures in low relief areas. Professional exterminators were called in to remove the nests so that conservation could proceed. After the final rinse, the sculpture was dried with soft towels to prevent minerals in the water from depositing on the surface through evaporation. These mineral deposits detract from the sculpture’s patina and are difficult to remove.

Waxing: Stanford student Bryce Cronkite-Ratcliff heats the metal surface before applying micro-crystalline wax (left), a detail of before and after waxing, and the Conservation Crew at work buffing the new wax coating.

Waxing: Stanford student Bryce Cronkite-Ratcliff heats the metal surface before applying micro-crystalline wax (left), a detail of before and after waxing (center), and the Conservation Crew at work buffing the new wax coating (right).
Crew from left to right Jocelyn Chan (small ladder), Bryce Cronkite-Ratcliff (top of large ladder), Lauren Sweet (lower larger ladder), and Elizabeth Saetta (boom lift).

The next steps were wax application and buffing. The wax application is ideally done when the metal is warm, so that the wax melts and then coats the metal surface thoroughly and evenly. To get the most complete and successful application, propane torches were used in conjunction with the heat of the afternoon sun. The conservator’s tool kit included: a tinted micro-crystalline wax thinned with mineral spirits, brushes, propane torches, and nylon stockings. Once the wax was applied, the spirits evaporated, leaving only the protective, hard, solid wax layer behind. At this point the surface was thoroughly buffed, a job for which the soft, fine nylon of women’s tights is perfect. Buffing smoothes brush strokes and irregularities in the wax application, and the resulting shine reveals the detailed dimension and relief of the sculpture.

Gates_DT_waxing detail with torch

At the top: Detail of the “The Three Shades” shoulder during treatment showing only the proper left shoulder coated, with wax and propane torch.

Before (left) and after (right) treatment details.

Before (left) and after (right) treatment details.

By the end of a long week, the conservation crew had washed and waxed not only The Gates of Hell, but also the statues of Adam and Eve that flank The Gates, and The Spirit of Eternal Repose that sits high atop a column nearby. The result is a cleaned, beautifully shining bronze—shielded from the elements with a protective coating so that these masterpieces may be enjoyed by generations of visitors.

washing spirit of eternal repose

Cleaning “The Spirit of Eternal Repose” by Rodin.

Totem Treatments

May 30, 2013

Stanford’s campus and the Cantor Arts Center is fortunate to have two totem poles in our collection carved and painted by prominent totem pole artists of the Pacific North West. Boo-Qwilla by Art Thompson was installed in Dohrmann Grove in 1995 and Stanford Legacy by Don Yeomans was installed in Canfield Court in 2002. Recently these poles underwent an extensive preservation and restoration effort.

One of the most basic needs of an outdoor work of art, like Stanford’s totem poles, is preventative maintenance in order to keep the sculpture looking its best, and even more importantly to maintain its structural integrity and overall condition.

Stanford Legacy before (left) and after (right)

Stanford Legacy before (left) and after (right)

Boo-Qwilla before (left) and after (right) treatment

Boo-Qwilla before (left) and after (right) treatment


The objective of this re-painting and preservation project was to clean the poles and restore them as closely as possible to their original appearance and the artist’s intent, and, to combat factors that could contribute to their deterioration.


Before any work was considered, the artists and their estates were consulted and artists John Livingston and his wife Maxine Matilpi were chosen to carry out the re-painting of the poles. The Native American Gallery of the Cantor Arts Center of Stanford University displays several of John Livingston’s carved and painted wood artworks and a beaded textile by Maxine Matilpi.  Livingston has a long-standing relationship with both of the totem poles artists.  He had worked closely with Art Thompson during his career, and served as assistant carver to Don Yeomans during the creation of the Stanford Legacy pole. More information about their work can be found in these short videos of John Livingston and Maxine Matilpi in the Native American Artist Series, produced by the Quintana Galleries.


A professional conservator with an expertise in totem pole conservation was consulted before any intervention.   Andrew Todd visited to inspect the poles and weigh in on the current condition of each, in order to provide treatment recommendations based on his experience treating totems and museum background.  Andrew lives and works in Canada, where totem poles are abundant, and travels the world to treat totem poles in situ. For more information on his practice visit the AT Conservators website.

Stephanie Chan cleaning the top of Stanford Legacy

Stephanie Chan cleaning the top of Stanford Legacy

The first stage of the treatment was a thorough cleaning. The poles were washed with a mild detergent and soft bristle brushes to remove any dirt or bio-growth in preparation for a fresh coat of paint.  Before the painting could be done an additional application of wood preservative was necessary to deter wood boring insects. Both of the totems had previously been treated in this manner, however because the preservative is water-soluble, washing the poles may have removed some of the previous application.  To ensure the wood was protected a 10% solution of Timbore, a borate-based wood preservative, was applied to the poles using a garden sprayer.  The application was focused on the end-grain where the wood is most absorbent, allowing capillary action to carry the solution throughout the totem pole and disperse the protection. Once the poles were clean and treated with a preservative the painting could begin.


John-Livingston & Maxine Matilpi paint Stanford Legacy


Totem pole artists John Livingston and Maxine Matilpi traveled from Victoria, Canada to carry out this important work.  Good conservation practice makes every effort to maintain a connection with living artists, and in the case of totems, Livingston and Matilpi were an essential part of the project.   The intention of this project was to maintain the cultural integrity of the totem poles, while providing materials that will prolong the life of the artwork.  Much effort was put into identifying paints to replace the original paint formulas, which are no longer manufactured in compliance with current California V.O.C (volatile organic compounds) laws.   Livingston and Matilpi used exterior grade acrylic paints approved by each artist’s estate, which were selected based on their similarity to the original artist-applied paint and proven exterior durability.

Top of Stanford Legacy before (left) and after  (right) treatment

Top of Stanford Legacy before (left) and after (right) treatment

Conservation technicians Nicole Passerotti and Mauricio Antunano apply protective coating

Conservation technicians Nicole Passerotti and Mauricio Antunano apply protective coating

Preventative work:

A protective coating was applied after the painting was complete.  A handmade coating developed by the US Forest Service was chosen from a variety of available wood sealants because it was developed specifically for the protective coating of totems, and has proven successful in many case studies after years of exposure to the elements.   The coating was mixed just before application and applied with a hand sprayer to the surface of the poles.  The coating was carefully wiped from the painted areas to avoid creating an uncharacteristically glossy surface over the matte paint, where it could not be as effectively absorbed into the wood grain as on the unpainted surface.

Epoxy and dry pigments

Epoxy and dry pigments

Replacing previous repair: Deteriorated repair (left), removal (center) and new repair (right)

Replacing previous repair: Deteriorated repair (left), removal (center) and new repair (right)

A few areas of Stanford Legacy required more attention after painting and coating were complete. The proper left side of the figure holding a shield had a previous repair/fill that had deteriorated. This fill was carefully removed with chisels and a hammer. A new fill was created using epoxy bulked with sawdust and tinted with dry pigments to match the surrounding wood.  A few areas of delaminated and detached wood were adhered in their original positions using epoxy and clamping pressure from a nylon ratchet strap around the circumference of the pole (protecting the wood and paint from pressure and abrasion with a Mylar and cotton towel barrier).

Repair of delamination and detached piece using epoxy and nylon straps

Repair of delamination and detached piece using epoxy and nylon straps

Lastly, a new zinc cap was made to fit the top of Stanford Legacy. These types of caps are made for totem poles to protect against direct water penetration of the end-grain, and also because certain metals, such as zinc, provide ionic protection.  As the zinc corrodes over time the ions released act as a biocide, preventing the growth of small organisms that can be destructive to the wood. Not too long ago Boo-Qwilla received a similar treatment and was given a lead cap because lead ions possess similar biocide properties.

New zinc cap
New zinc cap

Also check out Stanford News article Pacific Northwest artists restore Stanford totem poles to their original grandeur