In this study, mortars from the citadel of Nabeul where studied using XRD in order to identify
their composition, and where investigated biologically to determine the role played by
microorganisms in there decay. Calcium carbonate (calcite – lime) is the main component of
the studied mortars; calcium silicate was also detected in addition to quartz and iron oxides.
The biological investigation detected some fungal flora amongst: Aspergillus ochraceus,
Aspergillus tamareii, Ascosphaera apis, Eurotium repens, Eurotium chevalieri, Doratomyces
sp and Cladosporium cladosprioides.