Before discussing the way forward for the study of (inorganic and organic) archaeological materials, it is first crucial to identify phases in which archaeological science (of which the study of archaeological materials forms a part) has developed.
Archaeology sits at the centre of an enormous web with links to other disciplines, including not just the biological and physical sciences, but also a wide range of disciplines in the humanities. Clearly scientific archaeology can be approached from a variety of viewpoints. The earliest work in archaeological science included the investigation of ancient technology. A paper published by Humphrey Davy in 1815 involved the investigation of a synthetic pigment made from copper, silica and natron, later known as Egyptian Blue. Another early publication, which was to set an unfortunate trend, although it appeared in Schliemann’s excavation report on Mycenae, was the appended chemical analysis of gold, copper and bronze from the site. These investigations in archaeological science are what might be discerned as phase I in the development of archaeological science: early stirrings’. At the time when they were carried out, these investigations revealed unexpectedly sophisticated aspects of ancient technologies, but these findings were not fully integrated with archaeology. Such investigations were, in a sense, ‘stabs in the dark’.
If we move forward in time to another discernible phase in the development of scientific archaeology, we find that, while, as in the past, analytical techniques were borrowed from disciplines like biology, physics and chemistry, new techniques were emerging which were designed specifically for the investigation of archaeological objects or materials. One such was the so-called milliprobe, the description of which was published in 1973 by Hall, Schweitzer and Toller. This device focused a beam of X-rays on inorganic materials. The development of the milliprobe was symbolic of the way in which the discipline advanced. Another advance in technique and instrumentation was also made in Oxford: the invention of thermoluminescence as a means of dating pottery, a useful technique which at the time was seen as a supplement to what was perceived as the principal technique, carbon-14 (Aitken 1974; 1990). With these new techniques coming on stream, and with the enormous potential which they offered archaeology, it is clear that this was an exciting growth phase, which we can label phase II: ‘the phase of invention’.
Modifications of existing techniques and the use of new techniques in archaeology, such as the introduction of accelerator mass spectrometry for dating minute samples, have both occurred subsequently, but nothing has occurred which is comparable to the phase of what can only be described as invention. Another advance (phase III), which can be labelled a ‘primary phase of archaeological science research’ (as opposed to a phase of purely scientific invention or the determination of certain technological characteristics) was exemplified by Colin Renfrew and his co-workers.
Here a substance (obsidian) which lent itself to chemical characterisation – partly due to the fact that man had not modified it at high temperatures – was analysed (see Section 6.6). For the first time, this work by Renfrew provided an example of where optical emission spectrometry produced a series of numbers which could be linked directly to distribution of the material. The use of this first technique was followed by a range of others – neutron activation analysis, X-ray fluorescence spectrometry and electron probe microanalysis. These analyses contributed in a new way. The research into obsidian from the Middle East and southern Europe clearly converted the measurement of the natural characteristics of a material into a reconstruction of man’s past behavioural patterns, coming to fruition in the 1970s. This was very different from either the investigation of a small number of archaeological samples to determine certain technological characteristics (phase I) or from the invention of new techniques (phase II).
This point about the interplay between science and archaeology and the ways in which science contributes to archaeology and archaeology to science will be returned to. Suffice to say, that when techniques of scientific analysis are used as investigative tools, the researcher must keep a clear head in defining precisely what it is that he or she is investigating archaeologically. In this case, the fact that obsidian could, in some cases, be sourced to the specific volcano vent which produced it meant that distribution patterns could be assembled around the origin of the obsidian. If one adds to this a consideration of the proportion of other lithics from the sites studied, the kinds of archaeological sites on which the obsidian was found (e.g. whether obsidian was processed there) and the ‘significance’ of the material to the society involved, a very powerful set of links between chemical analysis, society and technology is produced. It is these archaeological considerations which can make the difference between a complex interplay between science and archaeology and what can be a simple statement of scientific facts which sit at the fringe of archaeological endeavour. It is also clear that some research in archaeological science can be technique-driven and some driven by archaeology.
Subsequent scientific characterisation of obsidian use and distribution in Calabria by Ammerman has clearly shown that a solid archaeological framework – starting with a full survey of the archaeological sites in the region on which obsidian was found, consideration of the proportions of lithic material including obsidian on each site, distance from the source and the topography of the region involved – have clearly led to firmly-based models of obsidian use and distribution (see Section 6.6.2).
This phase, in which the archaeological significance of the materials played an important part, continued to strengthen and refine the links between archaeology and science. This surely is the essence of the full interplay between the best science and archaeology. Having emphasised how important the archaeological research framework must be, one should not lose sight for a minute of the critical importance of first-rate science. The conditions in which chemical analysis and dating (for example) are carried out must be monitored very closely – there is absolutely no room for a ‘black box’ mentality, or one would be accused of pursuing the rubbish in – rubbish out approach to science, based on only a partial understanding of the technique or poor conditions of sample preparation.
In reviewing Old World Archaeometallurgy edited by Andreas Hauptmann, Ernst Pernicka and Günther A. Wagner which was published in 1989, Roger Moorey (1991: 118) made the following comments:
Archaeologists have tended to expect miracles of materials science. Conclusions have consequently been drawn too fast from initial, necessarily narrow, databases. The due caution of the specialist has often been lost in cultural conclusions loosely based on their research. Powerful new scientific techniques from time to time open up exciting new horizons to archaeologists, who do not always fully appreciate how treacherously deceptive the results may be unless critically assessed over a period of time as much in geological and metallurgical as in cultural terms.
These comments underline clearly the tension that exists between the different groups of people who regard themselves as archaeological scientists – those with minimal understanding of the science, those with minimal understanding of cultural features and a spectrum of people in between. But it is surely what would be expected in such a multidisciplinary area of research and a relatively new one at that.
An excellent example of where a refined approach to the application of a technique to answering very specific archaeological questions is the use of accelerator mass spectrometry to investigate the re-colonisation of Europe after the last glacial maximum. Housely et al. have shown that by examining closely the contexts from which objects were derived and re-dating samples which appeared to be aberrant, a model for the re-colonisation of Europe involving clustered dates was produced, showing, even this far back in time, between 20K and 12K BP that they could identify expansions from refugia and work out the rates at which the expansions in a northerly and a westerly direction from southern and central Europe took place. The broad and important philosophical approach here was to attempt to date the event, not simply produce a series of independent dated points. So there is no doubt that such a carefully constructed research project based on clearheaded science with clear objectives, incorporating an environmental component and a careful consideration of other aspects of archaeological context must form the basis for future research in scientific archaeology. I would regard this project as an example of a new phase of research – phase IV: ‘holistic archaeological science’.
By reviewing some of the developmental phases of scientific archaeology from early stirrings, through phases of invention, a primary phase of archaeological science research to holistic archaeological science research it is possible to see how the interaction of otherwise discrete disciplines have led to the significant enrichment of archaeology. Funding of archaeological science research will always present a challenge, but there is no harm in striving for a bright future. The careful integration of the application of science to answering archaeological questions in a holistic approach to this area of discourse can produce by far the most powerful results with the greatest contribution to mainstream archaeology.
The case studies presented in this book mainly fall into this last kind of archaeological science research – holistic archaeological science — in which a range of approaches to the scientific investigation of ancient materials are brought together so that a clear and meaningful integration with archaeology occurs. The integration relies on successful communication between those involved, especially if they fall at opposite ends of the archaeological science spectrum. The way forward must be a further refinement of the interplay between science and archaeology.
Aitken, M.J. (1974) Physics and Archaeology, Oxford: Oxford University Press.
Aitken, M.J. (1990) Science-based Dating in Archaeology, London: Longman.
Davy, H. (1815) ‘Some experiments and observations on the colours used in painting by the ancients’, Philosophical Transactions of the Royal Society of London, 105: 97–124.
Hall, E.T., Schweitzer, F. and Toller, P.A. (1973) ‘X-ray fluorescence analysis of museum objects: a new instrument’, Archaeometry 15: 53–78.
Housley, R.A., Gamble, C.S., Street, M. and Pettitt, P. (1997) ‘Radiocarbon evidence for the late glacial human recolonisation of northern Europe’, Proceedings of the Prehistoric Society 63: 25–54.
Moorey, P.R.S. (1991) ‘Review of Old World Archaemetallurgy (eds A. Hauptmann, E. Pernicka and G.A. Wagner, Der Anschnitt, Beiheft 7, Deutsches Bergbau-Museum, 1989), Archaeomaterials 5, 1: 117–119.