First report on the provenance of some volcanic saddle-querns from the archaeological site of Tarxien (Malta)

The lava used to make saddle-querns recovered from the prehistoric megalithic temple complex of Tarxien (Malta), cannot have originated in the Maltese Archipelago because it consists entirely of sedimentary rocks. The National Museum of Archaeology (Malta) permitted the sampling of three damaged querns which were recognized among those reported from the site by the excavator, Themistocles Zammit in the early twentieth century. The volcanic samples were studied according to the igneous petrology methodology and belong to two different rock types and magmatic series, namely alkaline basalt (one quern) and calc-alkaline basaltic andesites (two querns). The petrographic classification of these millstones thus suggests a provenance from volcanoes which are represented by extrusives with a magmatic and plate tectonics geodynamic fingerprint of both ocean island basalts (OIB) and subduction zone-related volcanic rocks (SZVR). The provenance areas for the volcanic querns studied are the island of Linosa or the Hyblean Mountains (Sicily) for the alkaline basalt and the Aeolian Archipelago for the two calc-alkaline basaltic andesites. Accordingly, all the investigated grinding stones from Malta come from the neighbouring areas of the Central Mediterranean, thus confirming the existence of a strong exchange network between the Maltese Archipelago and the eastern Sicilian areas in the Late Neolithic (early to mid-3rd millennium BCE) and the Early Bronze Age (Tarxien Cemetery Phase ca. 2100 − 1500 BCE).