Abstract

Mortars from different stratigraphic units at Portilla Castle (Alava, North Spain) have been analyzed for mineralogical characterization before radiocarbon dating. The mortar binder at Portilla Castle is composed not only of neoformation calcite but also of double-layered hydroxide (LDH) minerals such as hydrotalcite and hydrocalumite. The mineralogy of several fractions of the binder has been analyzed to determine the granulometric distribution of minerals in the binder. The continuous monitoring of mineralogy during the extraction of different grain size fractions has been performed by using a scanning electron microscopy (SEM), X-ray diffraction (XRD), and thermogravimetric analyses (TGA). Hydrotalcite and hydrocalumite-bearing mortar binders give older ages than expected since they introduce dead carbon into the system.

Details

Title
Hydrotalcite and Hydrocalumite in Mortar Binders from the Medieval Castle of Portilla (Álava, North Spain): Accurate Mineralogical Control to Achieve More Reliable Chronological Ages
Author
Ponce-Antón, Graciela 1   VIAFID ORCID Logo  ; Ortega, Luis Angel 1   VIAFID ORCID Logo  ; Maria Cruz Zuluaga 1 ; Alonso-Olazabal, Ainhoa 1 ; Solaun, Jose Luis 2   VIAFID ORCID Logo 

1  Department of Mineralogy and Petrology, Science and Technology Faculty, University of the Basque Country-UPV/EHU, Sarriena s/n, 48940 Leioa, Bizkaia, Spain 
2  Department of Geography, Prehistory and Archaeology, Faculty of Arts, University of the Basque Country-UPV/EHU, Paseo de la Universidad, 5, 01006 Vitoria-Gasteiz, Spain 
First page
326
Publication year
2018
Publication date
2018
Publisher
MDPI AG
e-ISSN
2075163X
Source type
Scholarly Journal
Language of publication
English
DOI
https://doi.org/10.3390/min8080326
ProQuest document ID
2582831514
Copyright
© 2018 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.