Late antique and early medieval glass from the northern Venetian lagoon: New data from the archaeological site of Jesolo

Accurate microchemical characterisation was performed on a 4th-12th-century repertoire of coloured and colourless glass samples found in the archaeological excavation of Jesolo (ancient Equilus, northern Italy). The research aimed to improve the state-of-the-art knowledge of early medieval glass, through the characterisation of a stratigraphically very well-dated and homogeneous glass collection, further representing a unicum in the area of the western upper Adriatic. A representative sampleset of sixty-seven glass finds -including vessels, windows, tesserae and blocks of raw glass- was investigated by electron microprobe (EMPA) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). All samples are classified as soda-lime-silica glass made of impure sands and natron. In most cases, glass colour is imparted by iron naturally present in the sands, often counteracted by varying levels of manganese. The collection also includes numerous Co– and Cu-coloured glass. Colourless glass is Mn-decoloured or, to a lesser extent, Mn/Sb-decoloured. The proportion between fresh and recycled glass is almost equal. The provenance investigation has established that while Levantine imports are numerically limited, most materials can be traced back to the Egyptian area. Among the twelve samples assigned to the Levantine area, both Jalame-type and Apollonia-type glass has been identified in an almost equal percentage. Among Egyptian glass, a consistent group of 22 samples has been straightforwardly assigned to the HIMTa and, to a lesser extent, HIMTb groups. Both group 2.1 and 3.2 are clearly attested in almost equal amounts but individually less frequent than HIMT.