UV Fluorescence as tool to evaluate the biotic encrustation pervasiveness on under water amphorae near Crotone (Calabria-Italy)

Underwater ceramic sherds, found in the harbor of Crotone (Calabria, Italy), were analyzed with different analytical methods. The pottery fragments, mostly amphorae, are characterized by a great layer of encrustation on the surface. Archaeological information are very poor, no assumption about provenance and technology, these ceramics are only doubtfully dated to Medieval times. The petrographic (Optical Microscopy) and chemical analyses (X-Ray Fluorescence) on the ceramic of Crotone evidenced a strong compositional heterogeneity. Comparison with literature data supported two different production areas: Western (Southern Italy) and Aegean area. UV Fluorescence on biotic crusts, allows to evaluate the relationship between the biotic colonization and the ceramic paste and to trace the alteration pervasiveness due to the encrusting organisms.