Characterization of Clays Used in the Fabrication of Traditional Brazilian Ceramic Pans: Culture and Technique
The fabrication process of clay pans in the state of Espírito Santo, southeast of Brazil, is a recognized part of the country’s popular culture. In Goiabeiras, a district of the state capital Vitória, the traditional production of these pans is the source of income for many families. The technique used in these ceramic pans is of indigenous origin, characterized by manual molding, outdoor burning and application of tannin dye. The clay pans are distributed to several Brazilian states and are nowadays conquering the external market. For producing these pans, two types of, yellow and gray, clays are used. The actual source of raw material comes from the deposit of the Mulembá valley, where a concern on the possibility of exhaustion exists. The objective of this study was then to characterize these two types of clays and so contribute to the continuity of traditional clay pan production by knowing the characteristics of the local clays in case of an eventual need for their replacement. Chemical analysis, X-ray diffraction, particle size distribution, plasticity and thermal analysis of the clays were performed. The results showed that the clays are high plasticity kaolinite with considerable amounts of SiO2 and Al2O3 as well as of alkaline oxides, earth alkaline oxides and Fe2O3.
Lucio Salgado and Francisco Ambrozio Filho
M. C. B. Gadioli et al., "Characterization of Clays Used in the Fabrication of Traditional Brazilian Ceramic Pans: Culture and Technique", Materials Science Forum, Vols. 660-661, pp. 718-723, 2010