Archaeological chert artifacts from Atapuerca sites (Burgos, Spain): characterization, causes of decay and selection of compatible consolidating products


  • Ainara Zornoza-Indart Department of Painting, Faculty of Fine Arts, University of the of the Basque Country (UPV/EHU), Barrio Sarriena, s/n, Lejona, 48940, Spain
  • Paula Lopez-Arce University College London (UCL), Institute for Environmental Design and Engineering (IEDE), The Bartlett, School of Environment, Energy and Resources, Faculty of the Built Environment, 22 Gordon Street, London, WC1H 0QB, United Kingdom; Property Care Association, 11 Ramsay Court Kingfisher Way Hinchingbrooke Business Park, Huntingdon, Cambridgeshire, PE29 6FY, United Kingdom
  • Lucía López-Polín Institut Català de Paleoecologia Humana i Evolució Social (IPHES), Zona Educacional 4, Campus Sescelades Edifici W3, 43007, Tarragona, Spain



Archaeological chert artifacts, Consolidation, Nanosilica, Nanolime, Acrylic resin, Ethyl silicate


Chert tools from Galería and Gran Dolina Caves, located in the Sierra de Atapuerca site complex (Burgos, Spain), were characterized (macro-visual inspection, mineralogical phases, degree of crystallinity, soluble salts, surface morphology and optical surface roughness) and compared to chert samples collected from the surrounding Atapuerca mountain range. The chert tools were studied to determine their causes of decay and for selecting the most compatible consolidation treatments. It was found that samples solely containing quartz were not significantly altered and required little conservation treatment compared to those that contained quartz and moganite, which were more weathered and powdery, requiring consolidation. The efficacy of the consolidating products traditionally used by conservators (acrylic resin and ethyl silicate) to preserve these chert remains, together with novel nanoparticle-based products (SiO2 and a mixture of SiO2 and Ca(OH)2 nanoparticles) were assessed in this study. Changes produced by these consolidating products in the physical (surface morphology and cohesion) and aesthetic properties of the chert tools were evaluated using non-destructive techniques (peeling test, spectrophotometry and optical surface roughness), followed by destructive techniques, such as SEM and XRD.


Received: 2019-10-8
Revised: 2020-4-1
Accepted: 2020-4-9
Online: 2020-6-29
Publication: 2021-2-10


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How to Cite

Zornoza-Indart, A., Lopez-Arce, P., & López-Polín, L. (2021). Archaeological chert artifacts from Atapuerca sites (Burgos, Spain): characterization, causes of decay and selection of compatible consolidating products. Conservar Património, 36, 20–35.