Characterization and Alterations of Hispano-Moresque Tiles of 14th Century

The Tower of San Pedro's Church in Teruel, which was built in the Mudejar style in the 14th century, has its exterior walls decorated with glazed ceramics. Before its restoration, the composition and alteration of these glazes were analysed in order to correctly restore these tiles. Some samples of glazed ceramics were studied by SEM and OM. Significant alteration of these lead glazes was detected and shown to be caused by the formation of lead sulphate due to the use of gypsum plaster as a building material. Only green and honey-coloured glazed tiles were used to decorate the Tower. 7 refs.