National Science Foundation How Technology Changed Ancient Ceramics Karen Trentelman, Getty Conservation Institute, DMR Understanding how changes in ceramic technology allowed ancient artisans to produce increasingly sophisticated decorated fired ceramics will allow conservators, art historians and archaeologists to better contextualize ancient workshop practice - and may inform the development of next- generation ceramic technologies. This work is being led by Karen Trentelman and Marc Walton of the Getty Conservation Institute’s Collections Research Laboratory. Researchers at the Getty Conservation Institute and the J. Paul Getty Museum, in collaboration with Stanford University and the Aerospace Corporation, are uncovering links between ancient ceramic technology and artistic expression. In the 5th century BC, ceramic artists in ancient Greece changed their method of painting from “black figure” to the more refined technique of “red figure”. Using high-resolution spectroscopic techniques, differences in the chemical composition between individual elements of the design – some of which are as thin as a single human hair – are being identified. The results are leading researchers to understand how ancient artisans refined the clay slip compositions and controlled firing conditions to produce these remarkable ceramics. Examples of 5 th century BC black- (left, JPGM 88.AE.24) and red-figure (right, JPGM 96.AE.114) pottery. (Images courtesy of J. Paul Getty Museum.)

National Science Foundation Top: detail of 5th C. BC red-figure ceramic vessel. Below: Ca, Fe, K and Zn elemental maps showing variation between body, outlines and background materials; map area is 16 mm wide x 12 mm high. (Image credit: Marvin Cummings) Mapping Change: XRF Micro-spectrometry Karen Trentelman, Getty Conservation Institute, DMR Elemental distribution maps of red-figure ceramics acquired using a micro-X-ray fluorescence (XRF) spectrometer provide the ability to non-invasively measure compositional variations between the ceramic materials used to paint, for example, the line used to create the outline of the figure, the fine lines used to create details within the figure, and the broad washes of black used to create the background (see figure). This information is important in understanding what different materials were employed, and how, from which the ancient technology may be reconstructed. In addition, elemental maps such as the ones shown here are helping the research team identity suitable areas for detailed chemical composition and morphological study using high-resolution techniques such as ICP-MS, XANES and TEM.

National Science Foundation Crossing Cultures Karen Trentelman, Getty Conservation Institute, DMR Training the next generation of scientists to conduct research at the interface of science and art, two young researchers are participating in this project. Postdoctoral researcher Marvin Cummings (left), who just received his Ph.D. in materials science from Rice University, is being provided with the opportunity to experience working in three different types of research environments: cultural heritage, academic and industrial. Marvin is working on the XRF imaging portions of the project as well as designing a controlled oxygen fugacity furnace that will aid in the reconstruction of the black gloss technology. Giulia Poretti (right), a pre-doctoral student from the University of Turin in Italy, is spending a year at the Getty Conservation Institute to learn more about how the issues and ethics behind conducting scientific research in museum based laboratories. Above: Marvin Cummings (left) and Giulia Poretti (right) standing in front of the Getty Conservation Institute’s Bruker ARTAX scanning micro-XRF spectrometer. Left: Fragment (sherd) of ancient Greek pottery being examined using an optical microscope. (Images courtesy of Marc Walton)