POTENTIAL MAGNETIC SUSCEPTIBILITY AND FRACTIONAL CONVERSION STUDIES OF ARCHAEOLOGICAL SOILS AND SEDIMENTS*

Potential magnetic susceptibility (χ_MAX) and, hence, fractional conversion (χ_CONV) are shown to be critical in interpreting low‐frequency mass‐specific magnetic susceptibility (χ_LF) data. Results presented from 29 sites in the UK and one in Hungary encompass six types of investigation: Quaternary sedimentary stratigraphies, archaeological contexts, surveys of old ground surfaces, topsoil surveys of lithic scatter sites, topsoil prospection surveys and ‘natural’ topsoils. The findings highlight the wide range of χ_MAX values that may be encountered; identify factors affecting χ_MAX; demonstrate that χ_CONV provides a measure of enhancement resulting from burning; and identify environments in which χ_LF analysis is likely to be problematic.