Ceramic building materials in early medieval churches in north-western France and south-eastern England. Application of luminescence dating to building archaeology.

Abstract

Amongst the dating methods that can contribute to building archaeology, it is the technique of stimulated luminescence applied to ceramic building materials (CBM) that is the focus of this study. The research reported in this thesis concerns the re-evaluation of an archaeological assumption surrounding the origin of CBM used in 9th, 10th and 11th century religious buildings of Normandy, Pays de Loire in France and Kent and Essex in England. Are the bricks used in the masonry structures Roman spolia or a novo productions? Dating techniques were scrutinized through a process of intercomparison work between two luminescence laboratories. This study highlighted the importance of knowing precise details of the sample’s original environment and the need for close examination of the mineral species used in the dating process. Results from thermoluminescence (TL) and optically stimulated luminescence (OSL) dating performed on 53 CBM samples from 12 churches of north-west France and south-east England showed that the practice of reusing Roman brick was commonplace in small parish churches, but also that brick/tile-making was not a totally unknown skill of the early medieval craftsmen as has long been supposed. Most importantly, by identifying that the building material is contemporary to the church, a defined chronology emerges resulting in a new and extremely useful reference point in the history of early medieval architecture