Ancient Wall Tiles – The Importance of the Glaze/Ceramic Interface in Glaze Detachment

  • Marisa COSTA University of Aveiro
  • Paulo CACHIM University of Aveiro
  • João COROADO Institute Polytecnic of Tomar
  • Fernando ROCHA University of Aveiro
  • Ana VELOSA University of Aveiro
Keywords: ancient wall tiles, glaze/ceramic body interface, salt crystallization, glaze detachment


One of the most severe pathologies suffered by early industrially produced tiles in Portugal in late nineteenth century is glaze detachment in wall tiles placed in the lower part of the façade. It is known that salts crystallize provoking the glaze detachment, destroying the waterproofing and the beauty of the wall tile and this is one of the crucial factors towards this occurrence. The present work questions the importance of the thickness of glaze/ceramic body interface, in what concerns glaze detachment provoked by salt crystallization. SEM-EDS was used to perform all the observations that lead to the conclusion that the exuberance of the interface between glaze and ceramic body has no influence in the resistance of the glaze to salt crystallization though time, being the porous network more determinant.


Author Biographies

Marisa COSTA, University of Aveiro

Department of Civil Engineering

PhD student

Paulo CACHIM, University of Aveiro

Department of Civil Engineering


João COROADO, Institute Polytecnic of Tomar



Fernando ROCHA, University of Aveiro
Department of Geociences
Ana VELOSA, University of Aveiro
Department of Civil Engineering