A pXRF analysis of historic brick chemical data throughout the lake Michigan Morainic region, United States

Abstract

Prior research has identified and grouped localized brick samples utilizing portable X-ray fluorescence (pXRF). This work asks whether historic brick samples across a multiple-state regional area can be reliably grouped based upon pXRF data. To answer this, pXRF readings (n = 718) were taken from sites or extant buildings (n = 36) in Milwaukee, Wisconsin; Chicago, Illinois; Hobart, Indiana; South Bend, Indiana; The University of Notre Dame, Indiana; and Zeeland, Michigan. Results indicate distinct chemical groupings that correspond with and represent different brick production sites. In some cases, it is possible to identify the use of brick of more than one chemical type within the same structure. This work is important because of the historic significance of bricks as an artifact class. A rich history of brick production has become a crucial factor in the community identity for many of these sites and the results of this project indicate that matching brick samples found in archaeological sites to their production site with pXRF is promising. The results from this work also indicate that historic bricks that are to be reused for contemporary repairs and construction projects can be accurately sourced based upon chemical data supplied by pXRF analysis.