By studying the tiles that decorate the Franciscan Convents of Olinda and Recife, both from the 17th and 18th centuries, it is possible to understand how this asset,which is part of Brazil's cultural heritage, stands out for its historical and aesthetic values, and how difficult it is to read all or part of certain historicised figurative panels. In this way, the current condition of the panels is analysed in relation to natural and/or anthropic interference in an attempt to identify the situations that make it impossible to read them.