Analytical Services

The Archaeometry Laboratory is one of only a handful of laboratories in the world that offer access to the three major analytical techniques used to characterize archaeological materials: NAA, XRF, and ICP-MS. These techniques each have their own advantages and disadvantages when dealing with specific matrices and archaeological problems. However, by providing access to all three techniques in one laboratory, we are able to increase their availability to archaeologists who would otherwise be unable to afford them. Further, by making these techniques available to the archaeological community, we hope to increase collaboration between archaeologists and analytical chemists.

Neutron Activation Analysis (NAA)

[Researcher Loading Samples for NAA] Neutron Activation Analysis (NAA) is a sensitive analytical technique useful for performing both qualitative and quantitative multi-element analysis of major, minor, and trace elements in samples from almost every conceivable field of scientific or technical interest. For many elements and applications, NAA offers sensitivities that are superior to those attainable by other methods, on the order of parts per billion or better. In addition, because of its accuracy and reliability, NAA is generally recognized as the "referee method" of choice when new procedures are being developed or when other methods yield results that do not agree. Worldwide application of NAA is so widespread it is estimated that approximately 100,000 samples undergo analysis each year.

Neutron activation analysis was discovered in 1936 when Hevesy and Levi found that samples containing certain rare earth elements became highly radioactive after exposure to a source of neutrons. From this observation, they quickly recognized the potential of employing nuclear reactions on samples followed by measurement of the induced radioactivity to facilitate both qualitative and quantitative identification of the elements present in the samples.

The basic essentials required to carry out an analysis of samples by NAA are a source of neutrons, instrumentation suitable for detecting gamma rays, and a detailed knowledge of the reactions that occur when neutrons interact with target nuclei.

Brief descriptions of the NAA method, reactor neutron sources, and gamma-ray detection are given here…

X-ray Fluorescence Spectrometry (XRF)

X-ray fluorescence (XRF) spectrometry is an elemental analysis technique with broad application in science and industry. XRF is based on the principle that individual atoms, when excited by an external energy source, emit X-ray photons of a characteristic energy or wavelength. Modern XRF instruments are capable of analyzing solid, liquid, and thin-film samples for both major and trace (ppm-level) components. The analysis is rapid and usually sample preparation is minimal. By counting the number of photons of each energy emitted from a sample, the elements present may be identified and quantitated…

Inductively Coupled Plasma Mass Spectrometry (ICP-MS)

[Quadrupole ICP-MS at MURR] Inductively Coupled Plasma Mass Spectrometry (ICP-MS) is a very powerful tool for trace (ppb-ppm) and ultra-trace (ppq-ppb) elemental analysis. ICP-MS is rapidly becoming the technique of choice in many analytical laboratories for the accurate and precise measurements needed for today’s demanding applications. Since 2000, researchers at the Archaeometry Laboratory have been using ICP-MS to address archaeological questions. We believe our newest analytic method, ICP-MS, holds great promise for chemistry-based provenance research…