September 15, 2003

Museum forges unique partnerships

Rachel Robertson

It’s hard to imagine how Delta Air Lines and Hershey’s Food Corp. could help the Carlos Museum analyze its artifacts, but the clever folks at the Carlos have come up with innovative collaborations that take advantage of the unique capabilities of each partner.

As the Carlos conservator, Renee Stein is in charge of contacting these companies to solicit their help in answering particular questions researchers at the museum have about artifacts. Of course, the museum has forged contacts across campus to get help; a well-known example is enlisting the help of medical researchers and technology in Emory Hospital to examine the Ramesses mummy using X-rays and CT scans. Stein also collaborates with people in the physics, chemistry and environmental studies departments.

“We certainly start at home when we can,” she said.

But some questions cannot be answered with equipment at Emory. One such challenge led Stein to Delta in search of an X-ray machine that could penetrate a bronze statuette of a man. The machines at the hospital simply are not powerful enough for the application.

At Delta, however, X-ray machines that can penetrate metal are used for Non-destructive Inspections (NDI) of plane parts to search for flaws such as fatigue cracks, wear or corrosion. “The [NDI] inspection is usually much more sensitive to very small defects that can’t be seen visually until they get much larger,” said Craig Schumacher, radiation safety officer at Delta.

The statuette in question, probably of Hellenistic or early Roman origin, had endured multiple repairs before it entered the museum collections. Because antiquities often are assembled from multiple works, it seemed possible that not all the parts originally belonged together.

To answer this question, Stein needed to look at the statue’s joinery, and the Delta NDI lab is expert in just this kind of work.

Although Delta’s staff has collaborated on other research projects involving plane parts, this was the first request they had for examining ancient artifacts, and they were happy to help.

“Helping Emory by providing the use of our facilities is just one way Delta supports the arts and education community in Atlanta,” said Schumacher. “Here at Delta, our employees believe in a strong spirit of giving, sharing, supporting and helping others in any way we can.”

“It was wonderful,” Stein said, “because they are used to looking at metal. They know their instrument well and are can look for all the same things that we look for.”

X-rays revealed both the original joints and old repairs, and Stein was able to determine that the various parts of the statuette truly belonged together. That original visit to Delta occurred more than three years ago, and since then Stein has returned twice more to examine other metal artifacts.

“Each time has been very exciting for us and generates a tremendous amount of interest among everyone here,” Schumacher said. “We enjoy the break from our day-to-day work and the challenge of helping to reveal the secrets that are sometimes hidden within these fantastic works of art.”

Up at Hershey’s in Pennsylvania, senior staff scientist Jeffrey Hurst also is addressing a specific need for the Carlos. When museum curators began planning an exhibit on chocolate and encountered research questions, where else would they go?

Chocolate was first created in Central and South America, and it was not until after the Spanish conquest that chocolate was taken back to Europe. Much of the Americas collection at the Carlos contains vessels from Costa Rica, which is of particular interest to Carlos curators because, although cocoa trees are indigenous to the area, the Mexican and Guatemalan tradition of drinking foamy chocolate had not yet been proven for ancient Costa Ricans.

To test for the presence of chocolate in the residue of the pots, Hurst looks for theobromine and caffeine using high-performance liquid chromatography (HPLC) coupled to mass spectrometry. The process separates the material components, which allows them to be identified by their mass. Hurst uses HPLC in his work at Hershey’s but has now used his expertise to contribute widely to this specific area of archeological study.

“The work I have done with archaeological groups is surely not typical of my regular duties with Hershey’s,” Hurst said.

The first project he worked on stemmed from a phone call to Hershey’s toll-free consumer line by a research group looking for help with some samples from Guatemala. Through the published efforts of that work, word spread among archeologists and more requests followed.

“Last year, after our paper was published in Nature, I even had a phone call from some news organization asking me if I was the staff archaeologist,” Hurst said. “Obviously there is no such animal at Hershey’s.”

Although he may not be an archaeologist, Hurst is very familiar with academia. He has his own research program and also teaches graduate and undergraduate classes at Penn State.

“My work with organizations such as Emory is an avocation since it is ‘detective work’ I love to do, and every bit of information is a continuation on the learning path,” he said.

For the Carlos, it is another case of finding the right person for the job.

Of the six samples—“It looks just like dirt,” she said—Stein scraped from the bottom of pots, Hurst has detected theobromine and caffeine. Stein said they are now looking for other likely candidates to send to the chocolate factory.