Ceramic Analysis The Institute offers expert specialized technological ceramic analysis services to the archaeological community. Specifically, we cater to those folks who want to know if their ceramics were manufactured where they recovered and if not, where they were made?
Traditional archaeological ceramic analysis is typological. That is, the surface characteristics of the pottery sherds (general color, manipulation marks, decoration, etc.) are used to segregate sherds into different categories or types. Types record basic function (serving versus ceremonial wares) and can be associated with specific cultural groups. In addition, because the surface characteristics (like clothing styles) change over time, types are useful for assigning calendar dates to their associated sites, an important consideration when other dating techniques are not available. However useful, typological analysis alone is not appropriate for sourcing analysis, which requires data informative of where any one piece of pottery was manufactured. Therefore we offer a hybrid typological and technological analysis that sorts pottery artifacts into types but also documents the technological information necessary for sourcing ceramics to a geographic locale of manufacture.
Technological analysis focuses on paste composition (the clay and temper types potters selected for making the basic vessel) in order to document unique combinations that can subsquently be correlated with geographic locales of matching resource availability. Because of differential firing, use and depositional histories, the first step in data collection requires that all artifact samples (only a small corner of each sherd is used) undergo refiring analysis, which uses a temperature of 950 C to bring them to a comparable state. An oxidation atmoshere allows for full expression of the iron content, iron being the primary coloring agent in fired pottery. The refired clay color of each sample is recorded in Munsell Soil Color notation, which documents the number of different of clay sources represented in the assemblage. Subseuently a binocular microscope is used to identify categories of tempering materials, and that data is expressed in terms of generalized constitutents and size. Common tempering agents include coarse quartz sand, fine crushed sherd and coarse crushed igneous rock. The end result is the assignment of each sherd to a compositional category (which often repesents an individual vessel) that could only have been manufactured where those two resource types co-occur on the landscape.
An intervening assumption is that prehistoric potters in pedestrian societies did not transport the bulky clay and temper resources required for ceramic manufacture over significant distances, choosing instead to situate themselves adjacent to the resource base. This least cost assumption is derived from ethnographic studies and has been supported by subsquent archaeological studies. If identical clay and temper types of any compositional category occur in the immediate vicinity of the site, that contitutes a stong argument for local production.
The second step of analysis requires the collection of voucher samples of clay and temper sources from the immediate site vicinity for comparison with the ceramic artifacts. Temper type samples are either viewed directly with the binocular microscope or added to selected clay voucher samples and subjected to refiring analysis for comparison with archaeological ceramics. Clay voucher samples are refired and their resulting refired clay colors are compared directly with refired ceramics.
Our analysis experience is that in most cases ceramics were not manufactured where they are recovered, which always raises the question of where they came from and in extextion, how did they get there? The opportunity for ongoing research is why we offer our analysis services. In fact, the Ken Caryl Brown Ware Project (click on KCBWPRJCT in the left pane) began as a ceramic analysis contract.
And best of all, our ceramic analysis approach is widely applicable, and indeed has been sucessfully applied not only to cord marked ceramics, but also to various Ancestral Pueblo and Fremont assemblages. If our approach to ceramic analysis sounds interesting, feel free to drop us an email (Click on Contact Us) - we look forward to working with you.
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