Paper No. 16-2
Presentation Time: 1:50 PM
DETERMINING WHAT MINERAL AND ORGANIC PIGMENTS NATIVE PEOPLES USED, PROCURED, OR TRADED IN THE MIDCONTINENT OF NORTH AMERICA, CIRCA THE 12TH-13TH CENTURY: SCARCITY/ABUNDANCE/CHOICE
Ethnographically, we know that Native American peoples used both mineral and organic pigments to paint their houses, objects, and bodies. However, due to preservation, most of the archaeological examples of painted objects are limited to recipes described in these ethnohistoric accounts or rare preserved fabrics, rock art, or pottery. Due to the rarity of these preserved artifacts, material analyses to determine pigment recipes are infrequent. This project reports on another rarely preserved artifact, painted daub; clay applied to weather-proof houses that has been plastered and painted. Painted daub pieces with curvilinear designs were excavated by Glenn Black during WPA excavations of the Mississippian Period (12th
Centuries CE) Angel Site in Evansville, Indiana. Recent analyses indicate that the design motifs seen on the daub are similar to certain pottery motifs throughout the Ohio River Valley. The painted designs are in shades of red, white, black, gray, and a steel blue. As evidence of a colorful past created landscape, the pigments used to create the patterns are of interest as the material procurement and the scarcity/abundance of local pigment sources indicate human interactions with the landscape and between cultural groups.
Of particular importance to archaeologists is the application of minimally or non-destructive analytical techniques for the investigation of chemical and mineralogical identification of pigments in archaeological contexts. Non-destructive analyses were run on whole samples of the painted daub to minimize the impact on these rare artifacts. Portable X-Ray Fluorescence was run on all samples to determine relative ratios of the elements in the pigment and the background daub reading, indicating that a portion of the blue and black/gray pigments were organic. The samples with a single color field were then analyzed by X-Ray Diffraction to determine the minerals used for each pigment used in the painted designs. As pXRF indicated organic components in the paint recipes, RAMAN spectroscopy is being utilized to determine the as-yet unidentified mystery blue pigment. While this research is still ongoing, results indicate the procurement of similar pigments that are used in regional pottery, constructed earthen mounds, and rock art.