Technological Developments

Coinciding with changes in the way archaeologists looked at change in the past, there were major developments in the scientific techniques that allowed the identification of the movement of materials, and just as important, became more accessible to archaeologists. It was only in the mid-1950s that ‘characterization’ analyses took off after a meeting between archaeologists and chemists at Princeton to discuss the possibility of using nuclear research in the study of archaeology. This led to characterization analyses being undertaken at two laboratories - the Brookhaven National Laboratory in the United States, and the Research Laboratory for Archaeology and the History of Art at Oxford in England. Techniques deployed included Neutron Activation Analysis (NAA) and

Spectrographic methods. These studies were reasonably successful, being able to separate pottery ware from Asia Minor, Greece, and Italy, or different factories of Samian ware (see Chemical Analysis Techniques; Pottery Analysis: Chemical).

These studies laid the foundations for chemical analyses for the next four decades, in which tens of thousands of analyses using varying techniques were carried out on many types of objects including pottery, stone (obsidian, marble, chert, volcanic rocks), amber, and metals including coins. Apart from NAA, XRF, XRD, and spectrographic methods, techniques currently in use include Proton Induced X-ray Emission and Proton Induced Gamma Ray Emission (PIXE-PIGME), inductively-coupled plasma emission spectrometry (ICP), lead isotope analysis, and electron microscopy to mention a few. Major changes in the instrumentation of these techniques over the last thirty years have meant that more elements can be Analyzed with a higher precision. The choice of technique depends on availability to the archaeologist and cost (Figure 1).