Harvard Art Museums scientist Narayan Khandekar collects pigments and protects color’s role in our artistic heritage.

By Susan Dietrich

Cracked apothecary jars, wax-sealed test tubes, flasks with glass stoppers, old labels reading “Mummy.” Special cabinets within the Harvard Art Museums crowd with approximately 3,000 preserved color samples. Below each pigment is shelved the corresponding source material: rocks, shells, roots, insects — even a sample of said mummy. Together, the assembly constitutes the Forbes Pigment Collection, each item of which has a story and a serious place in art history.

As caretaker of this collection and director of Harvard’s Straus Center for Conservation and Technical Studies, Narayan Khandekar, with his staff and students, establishes standards for pigment identification that get shared worldwide. At the heart of it all is a scholar with an Aussie accent and infectious enthusiasm.

Which appealed to you first? The science or the art?

I became fascinated by art galleries while getting my Ph.D. in organic chemistry from Melbourne University. I kept looking for something that wasn’t in my chemistry classes. I hoped that conservation would be my way into the art world, so I got a post-graduate degree in painting conservation from The Courtauld Institute in London and worked as a scientist in galleries around the world.

And you landed at Harvard how?

I came here from the Getty Conservation Institute. When I tried to break into this business there was no clear path for a scientist to work in an art gallery/museum. Today, that path exists. At the Straus Center, I helped establish a three-year post-doc program for fellows to gain further experience analyzing and conserving objects in the museums’ collections.

Pigment is what? And how does it differ from paint?

Pigment is a small, colored particle. It’s what gives paint its color. It needs to be mixed with a binding medium that controls the flow properties: brush-ability, drying qualities, and/or matte-ness or gloss.

 

Tell us about some of your most exotic pigments.

Well, there’s carmine, which comes from ground cochineal beetles that live on cacti in Mexico. Before 1856, Tyrian purple was the only purple and was very expensive, very rare. It took 10,000 murex mollusks to make one gram of pigment. When the synthetic pigment mauve became available in the 1860s, the pent-up desire turned the late Victorian era purple!

Indian yellow was dried urine from a cow fed only special mango leaves. On a research trip to Australia in 2013, we met Aboriginal artists who really value black. They use manganese dioxide inside dry cell batteries as an additional black pigment.

Which project serves as a telling example of what the center can do?

Our conservators and conservation scientists combine art history with science to better understand the materials, how an artist uses them and how best to conserve them. One of our big public projects was the restoration of John Singer Sargent’s “Triumph of Religion” at the Boston Public Library. It required research into his aesthetic intentions, how he painted the murals, and his experiments with textures, applied surfaces and relief materials.

What can a pigment tell us about a work of art?

The Straus Center’s staff was asked to conserve five faded Mark Rothko paintings from Harvard’s own art collection. Rothko had used the unstable pigment Lithol Red, PR49, throughout each painting. We determined that the backgrounds were irreversibly faded but not the figures. Collaborating with Harvard’s department of chemistry and chemical biology, we found that the light-sensitive color had a calcium salt and the stable color had a sodium salt. For a 2014 exhibition, we digitally mapped the lost color and projected the missing color over the existing color so visitors could get an impression of what the paintings originally looked like.