Abstract
Portable X‐ray fluorescence (pXRF) is now widely used for detecting the elemental composition of a material. Elemental analysis can enhance archaeological interpretations, such as mapping, preservation analysis and identifying anthropogenic activities. However, validated and reproducible protocols for analysing archaeological soil are still required. The elemental concentrations detected with three sets of preparation methods were compared: in‐situ (no preparation), in‐field (analysing through plastic bags) and ex‐situ analysis (laboratory‐based preparation). Influential factors were also investigated: calibration parameter, moisture, homogeneity, sieve size and soil type. In‐field analysis attempted to improve reliability without offsite processing, but instead substantially reduced elemental concentrations and skewed the proportional distributions. Ex‐situ analysis significantly increased elemental concentrations and reduced variation. Proportional distribution was different between the three methods, but unchanged following homogenizing and sieving. These comparisons demonstrated that ex‐situ analysis maximizes detection and ensures consistent samples.
Highlights
Interpretations of archaeological excavations can be enhanced through the use of elemental soil analysis for chemical visualization
The absence of significant differences with processed compost samples suggested that archaeologists could use either calibration parameter for analysing soil, sample preparation still requires attention (e.g., McWhirt et al 2012 showed that Portable X-ray fluorescence (pXRF) analysis of compost showed better error rates and correlations with Inductively Coupled Plasma (ICP) after drying)
This paper sought to quantify systematically the influential factors on pXRF analysis of soil to identify and evaluate whether a necessity exists for sample preparation and the extent of preparation required
Summary
Interpretations of archaeological excavations can be enhanced through the use of elemental soil analysis for chemical visualization. Occupation phases and activities enrich the organic and calcium content of soil, and alter the distribution and forms of phosphorus present, distinguishing internal areas, domestic activities and food consumption zones (Middleton 2004; Migliavacca et al 2013). Elemental soil analysis allows mapping or surveying before excavation; Cannell et al (2018) used P, Ca, Fe and Cu to delimit burial zones of an unmarked graveyard in Furuland. A high carbonate or Cl content will inform the urgency of conservation and the desalination process required (Neff et al 2005). These applications show excellent capacity of elemental
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
