By Kari Schleher, Laboratory Manager
The seventh-century Basketmaker community that surrounded and included the Dillard site was home to Pueblo farmers who used a variety of pottery vessels for cooking and storage. As part of the Basketmaker Communities Project, Crow Canyon researchers are studying pottery recovered from the Dillard site—which is among the earliest ever made in the central Mesa Verde region—for clues to its manufacture and the social context in which it took place.
What were the “ingredients” used to make these early vessels, and where are those ingredients found on the landscape? Did residents of the Dillard site produce their own pottery from local materials, or did they import the materials, or even the finished pots, from areas more distant? Our lab staff has been working on a project that has already yielded some telling results.
The first step was to find out what pottery-making resources are available near the Dillard site. In 2012, Crow Canyon lab staff, Archaeology Research Program participants, and interns conducted a pottery resource survey in an area encompassing a square half-mile of our campus and an area adjacent to the Center. The Crow Canyon campus is located 2½ miles from the Dillard site.
We located and collected 32 clay samples and six possible temper sources during our survey. A seventh temper sample, igneous rock, was collected from an area approximately 6 miles from our survey area. (Archaeologists have found that it is more common for potters to go farther for temper than for clay.)
Next, we made 64 test tiles from our samples in different combinations and amounts of clay and temper. Each test tile was cut in half—one half to be fired in an oxidizing electric kiln and the other in a traditional pit kiln. So far, we have finished all the oxidized firings and one traditional firing in which 10 test tiles were fired (representing 10 different clay sources).
We then selected a sample of 34 archaeological sherds from the Dillard site to determine if they were made from the same clays we recovered during the survey. We removed a “nip” from each archaeological sherd and refired the nips to determine their final oxidized color.
Refiring small nips to a standard, high temperature is one method archaeologists use to evaluate the composition of clay. Refiring to a higher temperature than the pots were originally fired causes the iron present in the clay to oxidize and become red. An iron-rich clay will turn very red, and an iron-poor clay will be less red.
The refired nips were compared to similarly fired test tiles made from the clay samples collected during the resource survey. The color chart to the left shows the range of colors observed in the refired sherds from the Dillard site and in the clay test tiles. A number of the sherds and test tiles are similar in color, which suggests that we may have located many of the clay sources, or at least the geologic formation of clays, used to make the pottery found at the Dillard site. This in turn suggests that most of the pots from the Dillard site could have been made locally by residents using clays located within a short walk from their homes.