Technological characterization of Campanian pottery of type A, B and C and of regional products from ancient Calabria (southern Italy)

Sherds of Campanian pottery were studied by SEM-EDX. SEM images show that slips of Campana C are scarcely sintered and are thicker than the well vitrified coatings of Campana A and B and imitations of Campana B. Slips of products with a grey slip on a grey body are very thin and well vitrified. EDX analyses indicate that slips are richer in aluminium and iron, and poorer in silicon and calcium, with respect to the bodies. Higher potassium is also found in all of the coatings except those of Campana A. Here relatively high sodium makes the total alkalis comparable with those of the other products, except Campana C, where it is somewhat lower. Measurement of thermal expansion and X-ray powder diffractograms suggest that firing temperatures were mostly in excess of 900(o)C, but some samples of Campana C seem to have been fired below 800(o)C.