Using XRF in Archaeology
X-ray fluorescence is one of the main methodologies employed in archaeometry. It can help to identify the material composition of artifacts and understand how they were created.
Bulk chemical characterization of archaeological ceramics and sediments is essential for many purposes, from determining raw materials and identifying economic organization to assessing site use and evaluating preservation conditions. However, bulk analysis using instruments such as ICP-MS or INAA is often expensive and destructive.
X-ray fluorescence (XRF) is a widely used technique in laboratory settings. It is a nondestructive method for analysing rocks, minerals, and sediments. Unlike electron microprobes, XRF is capable of analysing large areas and can be portable. Moreover, it can be operated by an unskilled operator. Consequently, archaeologists can perform compositional analysis on artifacts in the field.
Using hand-held XRF, the elements of copper alloyed archaeological objects from the Roman Limes military fort of Vechten in The Netherlands were compared to their corroded surfaces and uncorroded cores. The results showed that the corrosion was caused by copper-alloyed metals and that the corrosion occurred over time.
The XRF results helped archaeologists understand how the materials were used, such as for cooking and drinking water, and the reasons behind different alterations to the surface of the object. It also helped archeologists identify the different types of stones that were used to make lithics. This knowledge can help them to reconstruct ancient life.
XRF (X-ray fluorescence) is a versatile analytical technique, particularly suited to assessing major elemental composition in metallic archaeological artefacts. It is deployed in situ and allows the measurement of objects with a limited or no damage to the surface. Moreover, the results can be obtained in a short time and at very low cost.
The bulk chemical characterization of archaeological materials is crucial to understanding how people used and moved through the landscape in the past. However, many traditional techniques for analyzing bulk compositional data are expensive, destructive, and time consuming. Consequently, portable XRF (pXRF) has become an increasingly popular method for assessing the composition of ceramics and sediment.
This webinar will discuss the challenges of archaeological ceramic compositional analysis with pXRF and explore approaches to robust measurement and data evaluation. In addition, it will discuss the calibration process and suggestions for best practices. The webinar will also include a 15 minute Q&A session where our experts can answer your questions.
X-ray absorption spectroscopy
Hand held X-ray fluorescence (HH-XRF) is widely used in industry and is slowly being introduced into archaeological/historical applications [1-5]. Special forms of portable XRF (pXRF) are also used for other analytical purposes, such as assessing corrosion layers in lead-based paints or evaluating copper alloys.
pXRF analyses do not require any sample preparation and can be conducted on a variety of samples such as rock, metals, and ceramics. The analysis results in a list of elements present on the surface of the object, giving information similar to a fingerprint. This information is useful in determining the materials of an artefact, as well as identifying possible sources of the material.
pXRF analysis is a powerful tool in identifying the source of an object’s raw materials. However, it is important to remember that pXRF involves the use of ionising radiation and is therefore subject to safety considerations. Those who operate the instrument should understand these issues, be fully trained in its use, and keep a record of all measurements they undertake.
X-ray emission spectroscopy
XRF analysis is a nondestructive and relatively quick technique to determine the chemical composition of materials. It is a valuable tool in archaeology because it can answer questions about construction technology and provenance, among others. It is also useful for dating a site and determining its age. It is an important tool for evaluating the accuracy of other techniques such as carbon dating and radioisotope analysis.
Various pXRF manufacturers promote their instruments as being suitable for archaeological and historical applications. However, the choice of X-ray tube and detector affects both portability and analytical performance. The latter is particularly critical for obtaining reliable trace element data, which is of significant importance for archaeological and historical materials characterization.
Quantitative XRF data consists of counts of specific X-ray fluorescent energies and is used to quantify the amount of an element in a sample. Qualitative data, on the other hand, is relative and only tells you which elements are present in a sample.