CHARACTERIZATION OF HISTORIC BRICKS FROM THE BICKFORD-GARRISON ARCHAEOLOGICAL SITE IN DURHAM, NEW HAMPSHIRE

Bricks from the Bickford-Garrison archaeological site in Durham, New Hampshire were characterized using X-Ray Fluorescence (XRF) and Scanning Electron Microscope (SEM), and the results of the XRF analysis was compared to a brick analysis from other historic seventeenth century buildings in St. Mary’s City, Maryland. K, Ca, Zr, Ti, and Ba values are similar which probably indicates similar clays and temper in the bricks. The K, Ca, and Zr values are higher in the Bickford bricks. Bickford bricks are 57% higher in K, and 38% lower in Zr than the St. Mary’s City bricks, which supports a different origin. Polished thin sections from four Bickford bricks were imaged using an SEM. Characteristics such as clay and mineral inclusions in larger mineral grains, regular linear fractures in mineral grains, elongate grains, and sub-angular grains were observed in multiple brick thin sections. Though the bricks differ visually, they have similar characteristics as revealed by the XRF and SEM data and were probably made in the same location.