A recently excavated medieval brick kiln at Saltsjö Boo, Sweden and the hXRF analyses of its products

The brick kiln at Saltsjö Boo is one of very few such structures known from medieval Sweden. Approx ¾ of the kiln has been excavated in successive short excavations from 2006 to 2011. Carbon 14 and TL (Thermoluminiscence) analyses indicate that the kiln has been in operation from c. 1250 to c.1450. This paper presents the results of the excavations and discusses the production of bricks and industrial logistics of the site.

To study brick manufacture and changes that occurred in composition of the raw material during over a period of 200 years we have used a handheld XRF, which offers great possibilities for chemical analyses on ceramics. A clear advantage of the method is that a large amount of samples may be analysed at low cost and during a short period of time. The data acquired at the analysis have been processed by means of various statistical methods from interpretations of scatter plots of two elements at time to multivariate tests. Of special interest has been to determine what may be considered as a normal variation in a sample from this type of context and explain anomalies in the material.