Cultural and technology elucidation of the Tupi-Guarani tradition through analysis of potsherds from Travessão do Rio Vermelho site (Santa Catarina - Brazil) by spectroscopy, SEM-EDS and chemometrics

Thiago G Costa; Antônio Sálvio Mangrich; Morgana H Z Hübner; Marcelino D de M Correia; Isabela da Silva Müller; Lucas Bond Reis; Sailer S Dos Santos; Juliana Salles Machado; Lucas Bueno; Felipe Rodrigues Dos Santos; Fábio Lopes

doi:10.1016/j.apradiso.2021.109957

Cultural and technology elucidation of the Tupi-Guarani tradition through analysis of potsherds from Travessão do Rio Vermelho site (Santa Catarina - Brazil) by spectroscopy, SEM-EDS and chemometrics

Appl Radiat Isot. 2021 Dec:178:109957. doi: 10.1016/j.apradiso.2021.109957. Epub 2021 Sep 21.

Affiliations

¹ Laboratory of Materials, Atelier for the Conservation-Restoration of Movable Cultural Heritage, Santa Catarina Culture Foundation, 88025-200, Florianópolis, SC, Brazil; Department of Chemistry, Federal University of Santa Catarina (UFSC), 88040-900, Florianópolis, SC, Brazil. Electronic address: atecor@fcc.sc.gov.br.
² Department of Chemistry, Federal University of Santa Catarina (UFSC), 88040-900, Florianópolis, SC, Brazil.
³ Laboratory of Materials, Atelier for the Conservation-Restoration of Movable Cultural Heritage, Santa Catarina Culture Foundation, 88025-200, Florianópolis, SC, Brazil.
⁴ Laboratório de Estudos Interdisciplinares em Arqueologia, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil; Museu de Arqueologia e Etnologia, Universidade de São Paulo, São Paulo, SP, Brazil.
⁵ Laboratório de Estudos Interdisciplinares em Arqueologia, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil.
⁶ Laboratório de Materiais Inorgânicos, Departamento de Química, Universidade Federal de Santa Maria, 97105-900, Santa Maria, RS, Brazil.
⁷ Laboratório de Física Nuclear Aplicada, Departamento de Física, Universidade Estadual de Londrina, 86057-970, Londrina, PR, Brazil.

PMID: 34592693
DOI: 10.1016/j.apradiso.2021.109957

Abstract

Ceramic fragments can provide an insight into the ancient culture and practices of groups of humans and their way of life (technology, cultural identity, social organization, habitation and economy). Scientific analysis can be used to obtain information on the ceramic production process, as well as the specificities of the material employed. In this research, all samples of archaeological potsherd from the Tupi-Guarani tradition were analyzed in order to identify and to characterize the structures, morphologies and the elemental composition by using by scanning electron microscopy (SEM-EDS) and multivariate statistical methods (PCA and HCA). FTIR spectroscopy revealed the presence of an organic residue in three samples along with carbonates, clay minerals, quartz and hematite. In addition, the presence of the stretching attributed to water molecules in crystalline systems was observed. Also, the presence of TiO2 in the anatase polymorphic form was detected using μ-Raman spectroscopy. These results indicate a firing temperature of between 800 and 1000 °C. In relation to the morphology, all samples revealed amorphous structures presenting isolated and heterogenic particles of different forms and sizes, and the EDS spectrum confirmed the elements present in the molecular structures elucidated by vibrational spectroscopy. The multivariate analysis has confirmed the correlation between the elemental compositions of ceramics collected from two different sites: a mountain region and a coastal area in Santa Catarina State, Brazil.

Keywords: Archaeological ceramic; Clay; Electronic microscopy; Multivariate analysis; PCA and HCA; Spectroscopy.