It is the Aspe-Pantano area of Elche, next to the quarries of Ferriol
They extracted white and red clays to analyse between 300 and 400 combinations
The study reveals the high technological development that these potters from Illice had over 2,000 years ago
Alicante, 3 August 2017
The Lady of Elche was discovered in the archaeological site of the Alcudia on 4 August 1897. Now, a multidisciplinary team made by researchers of UA La Alcudia University Foundation for Archaeological Research and the departments of Agrochemistry & Biochemistry; Earth & Environmental Sciences; and Orgnaic Cheistry, with the support of the Universidad de Alicante Research Technical Services have performed a reserach work on characterisation of samples of La Alcudia using non-destructive techniques.
Results reveal that clays for the elaboration of the ceramics found in La Alcudia, which date from the 5th century to the 3rd B.C. come from the same place as the Lady of Elche, that is, the area of the Elche Swamp up to Aspe, next to the quarries of Ferriol. From this same place, the members of the project research team have extracted the material for analysis, after consulting one of the participants, geologist José Enrique Tent Manclús, who gave the directions on where to remove the strata. Juana Jordá and María del Mar Cerdán, part of this multidisciplinary team and specialists in Agrochemistry, are aware of the advantages of the several disciplines its members are working at. "It has helped us move forward in things that none of us could have done on our own," they confess.
The project has focused on the chemical and characterisation analysis of the ceramic fragments from La Alcudia using non-destructive or micro-destructive techniques, such as X-ray or infrared fluorescence. The analyses allowed researchers to identify, for the first time, the production made in the area of Elche. Experts have verified how all the pieces from Illice have common features, being white and red the regular mixture of clays for the elaboration of ceramics. As for firing temperatures, between 600 and 700 degrees Celsius were established. Also, they could detect if any pieces were detected outside this area, however they conclude that the clays used were located in the area of the Aspe and the Elche swamp.
The graphs with the results of La Alcudia fragments of ceramics and bricks from Agost reveal the same facts. Juana Jordá confirms that they have even located the quarry from where they extracted the clays for bricks, that comes from the ceramics Virgen de las Nieves in Agost. "We have found such an accuracy in one sample; in others we see great similarities."
Establishing the "fingerprint or DNA" of these ceramic productions will allow researchers to distinguish whether some fragments found in other archaeological excavations in the Mediterranean area come from the ancient Ilici, as researcher involved in the study Juana Jordá states.
Ana María Ronda Femenia and Mercedes Tendero Porras, the two archaeologists working at La Alcudia have also participated in the project. Ronda explains the high quality of ceramics and the many kilns existing in Iberian times. However, in order to determine where these muds come from, it would be very helpful to analyses the chemicals of the ceramics form different periods." They thus verify how local ceramics of different times do coincide in those chemical analysis, "which allows us to verify that the mud was collected from very similar points at different periods", as she confirms.
Archaeologists wanted to check what the analyses reveal: that the muds of the local ceramics have been extracted from the points found. To do so, they introduced ceramics for the rest of the members of the research project to analyse, without telling them the origin of these; "We know some of them are from France and from southern Italy," Ana Ronda said. "The archaeological data seem to confirm the result they are getting from chemical analyses," Juana Jordá said.
Researchers looked for clay quarries in the province which also came from La Alcudia influence areas. After that, they performed the sampling; They made pastas and compared them with the ceramic pieces that the archaeologists of the site had given them, which were more than fifty samples; they were contextualized and dated. They saw this way that mixtures were not pure, so they were mixing them up until until they found some similarity.
Altogether, they mixed up five white clays and three red ones in different ratios and different cooking temperatures (between 500 and 900º C), to get between 300 and 400 combinations. These samples were analysed by means of X-ray (RX), RX diffraction and infrared fluorescence. They also introduced some pieces that are not from Elche and that the archaeologists themselves added without letting the researchers who should do the chemical analyses know.
They verified that all the pieces from Elche have common features, being the mixture of white and red clays the regular combination for the elaboration of ceramics, and that cooking temperature can be between the 600 and the 700º C. As stated by Jordá, the clay is changing and transforming depending on the temperature at which it is fired.
Moreover, it is possible to know if any part outside this zone is detected. However, the study reveals that the clays used are located within the zone of the Aspe and the swamp of Elche. Jordá explained that "it is assumed that the higher temperature the kiln reaches, the more modern the piece is, except for the moments of civilization falls or depression." The firing temperature of the kiln can also be obtained, as it depends on the minerals contained in the piece. To give an example, this expert in Agrochemistry said, carbonates disappear in the clay at 700 degrees.
A thin layer of white clay is frequent on the painting, over which iron oxide is used to paint on it. The analyses suggest that they took the red clay to prepare the piece, fire it and then they added a layer of white clay, firing it for the second time. According to Jordá, this increases porosity in the clay. Once this ceramic was obtained they painted it with iron oxide. This is why the the green colour is seen in the fluorescence analysis of RX, which is the pigment of iron oxide".
Juana Jordá stated that this mixture of red clay with white clay "is pure technology. The fact that some of these pastes are very similar to those that are produced today is quite surprising and reveals the high technological development that these potters from Elche possessed more than 2,000 years ago", Jordá said. "In order to give it a texture and the physical properties that served for what they wanted, they mixed the different clays together, because they knew the physical properties of the clays," Mar Cerdan Sala, another of the agrochemical researchers of the study, said.
The study has also carried out an analysis of chemical composition. Strontium is an element found in the mineral Celestina and it can be easily found in the province of Alicante. Researchers have confirmed that all the samples had strontium.
Ronda makes a positive analysis of the study as it achieves a "ratio of what the ceramics from are like and a way to verify the origin of the ceramics found in other different areas." As the archaeologist explained, these verifications are made by analysing the painting.
"Caracterización de muestras de La Alcudia mediante técnicas no destructivas" is the fourth project awarded by the University of Alicante Office for Research & Knowledge Transfer , and it is included in the budget of the University of Alicante 2016 Programme for R&D+i Promotion to perform archaeological projects to be carried out at La Alcudia. The project has been awarded €3,000.
Images courtesy of Juana Jordá.
IMAGE 1: RX analysed Alcudia Ceramic
IMAGE 2: RX concentration of Silicon Alcudia ceramics
IMAGE 3: RX iron oxide concentration (in green) Alcudia ceramics
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