PROVIDENCE, R.I. [Brown University] — For much of human history, the color blue was a relative rarity in artistic expression. It’s essentially absent from prehistoric cave art — and a price tag for blue that was larger than that for gold limited its use for thousands of years more.
The reason boils down to chemistry.
While the pigments and dyes needed to make reds, yellows, greens and browns occur commonly in nature, stable blue pigments are rare. Egyptian blue — the world’s first synthetic pigment — was created in 3100 B.C.E., but blues still weren’t readily available until the 19th century when modern chemistry finally enabled mass-production of new pigments like cobalt and synthetic ultramarine.
The historical significance and complicated chemistry of the color blue have given it a major
role in Chemistry and Art, a course offered this semester in Brown’s Department of Chemistry by teaching professor Li-Qiong Wang. The course aims to explore key concepts in chemistry in the context of art and art history. Students study the chemistry of pigments and paints, dyes and stains, pottery and porcelains, as well as gemstones and jewelry. And as they learn the chemical underpinnings of artistic expression, they get to make art objects of their own — often using raw materials they synthesize themselves.
Wang says she hopes the class offers a new way for students to look at both art and chemistry, and more importantly, to get them to reach across both the sciences and the humanities.
“It’s just a very interesting intersection,” Wang said. “We’re not a chemistry class, and we’re not an art class. We’re looking at art, art history and art objects through the chemical lens. What I really want to do is train students how to do interdisciplinary thinking — how to collaborate with and learn from people who have very different backgrounds.”
New activities, new insights
Wang started to develop the class in 2018, with the help of two undergraduate students, Isabella Lovelace and Iris Peng, supported by an Undergraduate Teaching and Research Award (UTRA). Wang knew she wanted a class on chemistry and art, and that she wanted it to have plenty of hands-on projects, but she was open to what those projects might be. So she turned her UTRA students loose to explore possibilities.
“I told them, ‘Don’t look at anything and don’t worry about the literature or what’s already been done,’” Wang said. “Just come up with things on your own.”
The result was a series of novel activities in which students make their own pigment, which is then combined with different binders to make paints. Students create a ceramic glaze using their synthesized pigments, then examine color differences that emerge as a function of glaze firing temperature. In another project, students experiment with cyanotype — a photographic method that uses chemicals combined with ultraviolet light to create blue monochrome prints. They then tone the prints to brown or black to investigate the underlying chemistry of the toning process, comparing it with the chemical principles involved in making iron gall ink.
Those activities are interspersed with guest lectures from people in specialized fields. Leslie Welch, an associate professor of cognitive and psychological sciences at Brown, talks about the neurological underpinnings of human color perception. Ingrid Neuman, a conservator at Rhode Island School of Design (RISD), gives a lecture on art conservation. Technical staff members introduce students to X-ray fluorescence (XRF), X-ray diffraction and Raman spectroscopies used to analyze chemical compounds found in paintings and other objects.
