One approach undertaken in the CoFIPoMS project is the study of locally found materials which could have been used for the manufacture of pottery. The aim is to better understand the availability, composition, and variability of local sources, as well as the constraints presented by the different raw materials. This allows archaeologists to make inferences about where people used to source their material, and how they would have transported and processed clay and temper.
CoFIPoMS is reviewing the literature on local geological materials in Malta. This includes publications on a variety of topics such as data on local clay sources, traditional knowledge on the sources and use of raw materials, contamination, and other related topics. Unpublished data are also being sought and identified.
Building on the MaltaPot project, the CoFIPoMS team has collected clay, marl, and other geological samples such as terra rossa from around the islands of Malta and Gozo. The collection currently includes geological samples from at least twenty-five locations. The project aims at making these data and samples accessible in the future.
As part of a visiting internship project, eleven clay samples from one location have been analysed using X-Ray Diffraction after wet-sieving. Partial grain size analysis was performed as well as the identification of a set of natural and non-natural inclusions using micro-Raman spectroscopy. The aim was to corroborate which minerals could be found in Maltese clays and find possible contaminants such as plastic particles (Humann, 2021).
As part of a Masters dissertation, a set of unsieved samples (clay, marl, and other geological samples) were analysed using X-Ray Fluorescence (Richard-Trémeau, 2022). The samples will be homogenised by crushing. The analysis of pottery and clay samples will be used to try to:
Projects:
Currently, the CoFIPoMS project team is collaborating with the Department of Biology on practicals and on an undergraduate dissertation on foraminifera found in Blue Clays. Foraminifera are observed in pottery thin sections and archaeologists have plenty to learn on their distribution and frequency across Maltese clay sources.
Student project: Abdilla, A. (In progress) Signatures of Foraminifera in the Blue Clay Formation of Malta, BSc dissertation. The University of Malta.
The CoFIPoMS team has additionally been collaborating with the Department of Chemistry providing samples and supervision on an undergraduate dissertation on the XRF analysis of sieved clays.
Experimental archaeology is an essential part of raw material studies.
Clay briquettes were formed to test the effects of different manufacturing conditions. Laboratory-based controlled experiments are being carried out to understand:
To date several sets of briquettes have been created using clay from one source, but additional work needs to be done before wider conclusions can be drawn. This is the first time this approach is being adopted in Malta.
Research projects are a great opportunity for students to get involved. One undergraduate student from the Faculty of Engineering has completed a dissertation on experimental firing (Xuereb, 2021). In this dissertation, wet-sieved clay from Il-Qolla (Rabat) was used to create briquettes which were fired at different temperatures, with different soaking times and firing atmospheres. Macroscopic and microscopic analysis, X-Ray Diffraction, Knoop hardness tests and SEM/EDS analysis were performed on a subset of samples.
Project:
K. Coste, an intern visiting from the University of Edinburgh, created and recorded experimental samples including briquettes made of Globigerina marl derived soil or of Blue Clay manufactured with sea water or with purposely created grog. These are still to be fully studied. Additional samples are being manufactured and created to test specific hypothesis on raw materials.
