Ceramics for the Archaeologist by Anna O. Shepard
In the winter of 1933, future Carnegie Science archaeologist Anna Shephard travelled from Santa Fe’s Laboratory of Anthropology to Carnegie’s Geophysical Laboratory in Washington, D.C., where she spent three months learning to see rocks like a geologist.
Using advanced petrographic analysis, a microscopy technique geologists used to identify minerals in thin slices of rock, Shepard suspected she could unlock secrets hidden in ancient pottery. That hunch would shape the rest of her career and lead to the publication of Ceramics for the Archaeologist, the fourth object in our 125th-anniversary series.
Born in Merchantville, New Jersey, in 1903, Shepard earned her bachelor's in anthropology from the University of Nebraska in 1926. After a stint as Curator of Anthropology at the San Diego Museum, she took up a research associate position at the Laboratory of Anthropology at Santa Fe. That’s where she met prominent Carnegie archaeologist Alfred V. Kidder in 1931, which would begin a productive 37-year affiliation with Carnegie Science. Kidder, the chairman of Carnegie’s Division of Historical Research, invited Shepard to collaborate on the study of a vast collection of pottery he had recovered at Pecos, New Mexico, over several seasons of archaeological excavations.
Keen to explore the possible utility of petrographic analysis in pottery, Shepard jumped at the opportunity to subject the Pecos pottery to such rigorous laboratory techniques. Her experience at the Geophysical Laboratory, facilitated by Kidder, only intensified her budding desire to bring laboratory methods into archaeology, a field that—in her view—badly needed the "impersonal, experimental, and quantitative" point of view of the sciences.
Over the following years, Shepard spent much of her time collaborating with Kidder on Carnegie projects on the pottery of the American Southwest and Mesoamerica, and in 1938, she was officially appointed as an Investigator in the Carnegie Division of Historical Research. For the next three decades, she worked largely alone from a laboratory set up in her home in Boulder, Colorado. Her position with Carnegie provided long-term material support and an ongoing connection with the archaeological and scientific communities, which supplied a steady supply of ceramic artifacts for analysis and study.
Shepard’s technique of shaving a thin sample from a pottery glaze, mounting it on a slide, and examining it under a microscope to identify the mineral grains it contained was painstaking, but worth the attention to detail. These hidden petrographic and chemical fingerprints revealed a previously untold story: by matching them to known geological sources, Shepard could identify where the raw materials came from, allowing her to discern the existence of long-distance trade relationships between communities no one had previously connected. Further, the method allowed her to track how ceramic technology evolved over time, piecing together a timeline of innovation across cultures.
One of her most intriguing findings, the "Maya Blue problem," demonstrated the power of applying such analytical approaches to solve technical problems in archaeology. Archaeologists had been puzzled by the source of the vivid blue-green pigment found on some Maya pottery, but Shepard finally demonstrated it wasn't a natural mineral at all. Rather, ancient potters had invented a process for making a blue pigment.
Shepard explained her methods of analysis in her celebrated treatise, Ceramics for the Archaeologist, which Carnegie Science published as Monograph 609 in 1956. At 414 pages, it was comprehensive, covering the properties and sources of ceramic materials, ceramic practices, analytical techniques, and pottery classification from both cultural and functional perspectives. It treated pottery as scientific evidence, rather than simply items to be collected and cataloged. The volume quickly became a bestseller, requiring a second printing a year after publication, followed by another nine reprintings over the next three decades. It remains a classic standard in archaeology today.
Shepard retired from Carnegie in 1968 after also working part-time as a geologist with the U.S. Geological Survey beginning in 1957. The Division of Historical Research, where Shepard spent her Carnegie career, no longer exists. But Ceramics for the Archaeologist forever stands as a testament to her pioneering efforts to apply scientific analysis to provide a more comprehensive picture of the past.
