Simple to complex 3D measurements for the quantification of knapping parameters.
Ongoing research on Middle Neolithic flint technology
In this blog post we report on our experience using 3D capture and analysis technologies for the study of a particular type of Neolithic flint knapping.
When we began our research, the scientific objectives were broad: we wanted to better understand the agro-pastoral societies that occupied the northeast of the Iberian Peninsula between the late fifth and the early fourth millennium BC. In Iberia, this time bracket is commonly referred to as the Middle Neolithic.
One characteristic of the Middle Neolithic (ca. 4200-3600 cal BC) in the northeast of the Iberian Peninsula is the relatively sudden apparition of very elaborate funerary structures with rich grave goods. This phenomenon is called “Cultura dels Sepulcres de Fossa” (cat.) and has been compared to other European phenomena such as the Chassey, Cortaillod or Lagozza cultures. So far, there are more than 650 burials dated within a period of five centuries. Whereas isolated graves or small clusters of graves (5 or less) are the most typical occurrence, some necropolises that include more than 25 graves are also attested. Among them we would like to highlight the particular case of Bòbila Madurell-Can Gambús, a necropolis with approximately 180 burials.
The cores knapped on barremian-bedoulian flint
Some of the grave goods from the “Sepulcres de Fossa” were imported from very remote areas and/or required a great deal of investment in their production, suggesting very complex networks of exchange across Western Europe and the northern Mediterranean Sea. It is within this context that we can place the appearance of barremian-bedoulian knapped cores and blades in many tombs. Cores and products knapped with this flint arrived from Provence in South-eastern France.
Previous studies have determined that the cores made from this flint received careful heat treatment and that they were knapped in a very characteristic and standardized way for blade production by means of pressure techniques. In addition, studies suggest that most of these cores were not exhausted when they were deposited in the graves.
Lines of 3D research
Despite the fact that former studies of these cores and blades were quite successful from a scientific and analytical point of view, we believed that particular issues could be better addressed using a 3D analysis of digital models of the artefacts. We therefore our study on (1) our understanding of lithic “know-how” and experimental archaeology, (2) a technological and holistic perspective on lithic resource management by Neolithic groups, and (3) the 3D capture and creation of 3D models to further progress in our study of these archaeological materials.
Materials, methods and extracted data categories
So far we have scanned 71 cretaceous flint cores which includes nearly all of the artifacts of this category recovered during the last two centuries of archaeological work in the region. The cores were digitized using a Breuckmann Smartscan 3D structured-light scanner, and the models were produced with Rapidform© software. With this digital collection as a basis, we started to develop a series of protocols for producing graphical information, for taking measurements and for extracting other data from the cores. In this sense, We generally went from simple to more complex, as is demonstrated in the following list:
- Conventional representation and drawing: With 3D models, a high quality conventional representation of a core can be produced in minutes, without requiring the physical item once the initial 3D capture was done.
- Qualitative “know-how” analysis: Visualization of 3D models has some advantages over physical observation, for example:
- The capability to delete the texture-colour information, leaving only the geometry of the object, which helps to analyze technical traits that are obscured by coloration and contrast.
- The use of precise, ad hoc lighting, using multiple lights, changing angles and adding complementary illumination to observe and highlight specific technical features.
- Extracting lineal features of cores and blades: sections, perimeters, convexities, etc.
- Measurement of surface and volume of both whole artefacts or of relevant parts or sections.
- Extraction of angular relationships between pressure platforms and flaking surfaces of cores, which is a fundamental criteria for technological lithic studies.
In our nascent experience with 3D scanning technologies and digital model analysis we have found that there are many advantages in using 3D technologies for lithic studies.
From a qualitative, “know-how” perspective, we have verified that 3D models are quite useful, because the digital manipulation of the model allows complementary analyses that can be combined with the study of the physical object.
And from a quantitative point of view, 3D based metrics represent a higher scale of speed, accuracy and flexibility. Angular, surface and volume data that could be very difficult to obtain otherwise are easily implemented through 3D model measurement and data extraction.
We believe that our ongoing application of 3D technology to the study of cretaceous flint cores and blades from the “Sepulcres de Fossa” will produce significant results in the future in a number of fields, such as: detailed technical features and knapping procedures, the specific degree of specialization and the possibility of variations or ramifications in the production of blades, volumetric analysis related to raw material transport and management, or the hypothetical amortized value of the cores, among others.
Bretzke K. & Conard N. J. 2012. Evaluating morphological variability in lithic assemblages using 3D models of stone artifacts. Journal of Archaeological Science 39, 3741-3749.
Gibaja J.F. & Terradas X. 2012. Tools for production, goods for reproduction. The function of knapped stone tools at the Neolithic necropolis of Can Gambus-1 (Sabadell, Spain). CR Palévol 11, 463-472.
Gibaja J. F. 2003. Comunidades Neolíticas del Noreste de la Península Ibérica. Una aproximación socio-económica a partir del estudio de la función de los útiles líticos. BAR International Series, S1140. Oxford.
Roig J., Coll J. M., Gibaja J.F., Chambon P., Villar V., Ruiz J., Terradas X., & Subirà M. E. 2010. La necrópolis de Can Gambús-1 (Sabadell, Barcelona). Nuevos conocimientos sobre las prácticas funerarias durante el neolítico medio en el noreste de la Península Ibérica. Trabajos de Prehistoria 67/1, 59-84.
Saragusti I., Karasik A., Sharon I. & Smilansky U. 2005. Quantitative analysis of shape attributes based on contours and section profiles in archaeological research. Journal of Archaeological Science 32, 841-853.
Terradas X. & Gibaja J. F. 2002. La gestión social del sílex « melado » durante el Neolítico medio en el noreste de la Península ibérica. Trabajos de Prehistoria 59/1, 29-48.
Millán Mozota is a specialized technician in archaeology at The Spanish National Research Council (CSIC) and associated researcher at The International Institute for Prehistoric Research of Cantabria. He is a specialist in bone tool technology, 3D scanning and model-building.
Xavier terradas is researcher of The Spanish National Research Council (CSIC), attached to the Department of Archeology and Anthropology of the Institution “Milá y Fontanals” of Barcelona. His research interests on Mesolithic, Neolithic, lithic technology, lithic raw matter analysis.
Juan F. Gibaja is researcher at The Spanish National Research Council (CSIC), attached to the Department of Archeology and Anthropology of the Institution “Milá y Fontanals” of Barcelona. His research interests on Mesolithic, Neolithic, funerary practices, use wear analysis.