Research Spotlight: Heather Graybehl on Late Roman Petrography
July 9, 2012
At the American School Excavations at Corinth, Heather Graybehl is currently conducting a petrographic study of Late Roman cooking pots, coarsewares, and amphorae from Panayia Field. She describes her work below:
Working in conjunction with Mark D. Hammond's ongoing dissertation research on Late Roman Panayia Field, my research aims to gain a greater understanding of ceramic production and distribution in the Northeast Peloponnese from the 4th-7th centuries AD. As a PhD student at the University of Sheffield in Archaeological Materials, I am a trained ceramic petrographer. In addition to conducting provenance studies, petrographic analysis allows me to identify important indicators of ceramic technology and production, such as raw material manipulation, fabric recipes, and change in manufacturing processes over time.
Heather processing clays as part of a clay prospection project.
I am currently focusing my study around the most common fabric found in the Late Roman assemblages- Corinthian cooking fabric. Corinthian cooking fabric comprises the majority of plain and coarse wares in the Late Roman period, including utilitarian, cooking, and transport vessels. The petrographic results revealed that this fabric does not change over the four centuries in question, and macroscopic analysis suggests that it may have been produced as early as the 1st century AD. Provenance studies suggest that this chert based fabric was produced in or around Corinth, as the geology of Acrocorinth and environs provides a good match for the raw materials used. Extended petrographic and macroscopic study of synchronic ceramics from sites around the Northeast Peloponnese, such as Nemea, Isthmia, and the Berbati Valley, revealed that this fabric is common throughout the region. Thus, I will continue sampling around the area to gain a greater understanding of the distribution patterns of Corinthian cooking fabric throughout the Peloponnese. The evidence gathered to date suggests that the fabric was a product of large scale manufacturing, with standardized practices of treating and mixing the raw materials, forming the vessels on the wheel, and firing. The fabric is so homogenous between the sites in question that there is no doubt that Corinthian cooking fabric was produced in one production center.
Heather (R), field director at Corinth in 2012, with regular member Leigh Lieberman (L)
and excavator Rosanna Valente (C)
Additionally, I am undertaking a large clay prospection study coupled with a program of clay treatment and firing experiments, done in conjunction with Guy Sanders and Mark D. Hammond, building on the previous work of Sanders, Ian Whitbread, and Louise Joyner. This study will help gain a greater understanding of the raw materials available in and around Ancient Corinth. This project includes sampling clays from a large variety of geological formations in the area, which we then process, and make into experimental briquettes. These briquettes will undergo firing experiments, and I will sample successful clays for petrographic analysis. The petrographic characterization of Corinthian clays will not only be valuable to this project, but also to other scholars studying Corinthian pottery, from all time periods.
As the Homer Thompson Fellow in the 2012-2013 academic year, I will continue this project throughout the year, as well as my PhD dissertation research on ceramic production and distribution in the Northeast Peloponnese in the Hellenistic period, focusing on assemblages from Nemea, Corinth, and Lerna. Ultimately, the culmination of my PhD and my Late Roman Corinthian study will allow me to see changes in raw materials exploitation, vessel manufacture, and distribution from the 4th century BC to the 7th century AD in Ancient Corinth and the greater Northeast Peloponnese.