New collaborations bring silver linings in the preservation of Yale collections

Thursday, September 1, 2016

The challenge of safeguarding Yale’s cultural collections has provided an unexpected opportunity for groundbreaking research at the Institute for the Preservation of Cultural Heritage (IPCH).

Throughout 2017, artifacts are being carefully situated in the endless rows of giant glass cases in the Yale University Art Gallery’s (YUAG) new Wurtele Collections Study Center – a 32,000 square foot space that is turning traditional ‘storage’ at Yale’s West Campus into unparalleled access to the Gallery’s collections for hands-on scholarship.

To the staff involved with the installation, housing artifacts in readily accessible display cases presents a novel set of challenges, and with them unforeseen opportunities to apply new techniques.

With a new ventilation system installed to provide only pure, dry air to the collection’s most sensitive metal objects, the Gallery partnered with the neighboring IPCH lab of Paul Whitmore to determine how to best monitor air quality over time. That’s when YUAG Project Conservator Elena Torok and her colleagues started to notice a worrying odor coming from the glass cabinets.

“We all go into galleries and marvel at pristine artifacts, and assume they just stay that way. But displays involve a huge web of expertise, and we have a great one at Yale,” says Whitmore, head of IPCH’s Aging Diagnostics Lab. The lab studies the causes of chemical and physical degradation in art objects to develop novel analytical techniques that can measure and monitor aging and changes as a function of time and environmental conditions.

Alongside IPCH colleague Rui Chen, Whitmore’s research has focused, among other areas, on the potentially harmful effects of corrosive gases released by degrading artifacts themselves. Using silver nanoparticles as sensors for reactive gases in art conservation applications, the scientists have previously found that these tiny silver films can be effective in the ‘Oddy test’ - used to test materials for their safety in proximity to cultural property - where they are much more sensitive indicators of corrosive gases.

The sensing response of silver nanoparticles is based on their special surface absorption properties, which impart a strong color to the nanoparticles. When the silver surface reacts with gaseous compounds, the nanoparticles appear bleached. Reactions are monitored by measuring the visible absorption with a spectrometer, with the reaction rate used to determine the concentration of the harmful gases.

Examining the odorous problem with Torok and her colleagues, Whitmore and Chen repurposed the nanoparticle technique, for the first time using it to analyze the cleanliness of the air and humidity supplied to the Wurtele Center’s glass cases.

“We happened to have the perfect tool to answer a different question, applying our research to a new challenge,” says Chen.

The technique performed in the same way as it had in previous studies of degrading artifacts, indicating that the humidification water supply was contaminated. Filters in the reverse osmosis filtration system have now been upgraded and the installation of precious artifacts can move forward.

This need for constant diligence and forward thinking mirrors advances in how we view and study cultural artifacts - from static, sealed glass cases, to today’s interactive, hands-on study facilities. “Many museums protect metal objects by using lacquers to coat them, or use desiccant materials to condition their environments, but this can be complicated, time consuming, and costly,” said Torok. “Collaborating with IPCH colleagues on site enabled us to prevent likely tarnishing of the newly installed artifacts.”

The immediate protection of cultural artifacts is a constant work in progress, but growing connections across Yale’s cultural heritage community are turning inevitable challenges and problems into opportunities for deeper understanding, and the creation of new techniques that are unique to Yale.