The innocuous ball of “Indian yellow” lying in a cabinet at the Straus Center for Conservation and Technical Studies at Harvard University has a hidden, colorful history. The yellow was made from the urine of cows fed exclusively on mango leaves and water, a diet that increases bile pigmentation. In the 19th century, Indian cowherds would collect the urine in earthen pots and create yellow sediment by evaporation, which would form the basis of the color, sold in the country’s metropolitan markets.
On a late winter afternoon, Dr. Narayan Khandekar, the director of the Straus Center, walks me through the Forbes pigment collection that he curates. It houses over 2,500 pigment artifacts from around the world. Although it’s not accessible to the public, a smaller installation immediately outside of the closed-door facilities is.
A walk by the cabinets is like spinning the color wheel and tracing the world history of pigments, across borders and trade routes, many with their origins in the Indian subcontinent. The history of blue, too, can be traced to the region, beginning with the discovery of the plant-based indigo dye centuries ago. Another avatar of blue would be birthed by yet again, in 2009. Dr. Mas Subramanian created an entirely different pigment of the color — YInMn Blue — in his Oregon State University lab.