Petrological footprints of the millstones of Megara Hyblaea (Sicily Island, Italy) highlight the human interactions with Mediterranean volcanoes

Abstract

A petrographic and geochemical study of several volcanic millstones, representative of 119 artifacts found in the ancient Greek colony of Megara Hyblaea (Sicily Island) and recording the grinding device evolution from the Archaic to the Hellenistic period, unravelled the volcanoes involved as quarrying and production areas. This was possible also through the comparison with available petrographic and geochemical literature data of ancient volcanic millstones found in the whole Mediterranean. Saddle querns, hopper-rubber, rotary Morgantina- and Delian-type millstones of Megara Hyblaea consist of lithotypes belonging to five magmatic series: Tholeiitic, Na-Alkaline, Tholeiitic Transitional, Calcalkaline and High-K Alkaline. A provenance from the Eastern Sicily, i.e. mugearites from Etna and basalts and basaltic andesites from the Hyblaean Mountains were recognized for all the four investigated grinding devices. By contrast, a sea-trade is involved for several saddle querns made of calcalkaline basaltic andesites and andesites lavas (Aegean Islands) and two Morgantina-type millstones consisting of a calcalkaline rhyodacite ignimbrite from the quarrying site of Mulargia (Sardinia). A wide millstone trade, both local (Eastern Sicily) or maritime (Central-Eastern Mediterranean) was thus constrained through six centuries, from the foundation of the Greek colony up to the destruction of the settlement at the end of third century BCE. Finally, Vulture Volcano (southern Italian peninsula) is the most probable candidate for the only leucite- and haüyne-bearing phonolite of the High-K Alkaline Series.

Evolution Magmatism of Nagasari Volcano Dieng, Central Java, Indonesia

“…The phenocrysts (77-85%) are fine to medium (0.1-0.2 mm) in size with a porphyritic and intergranular texture. This intergranular texture can be observed in the groundmass (Santi, Chaigneau and Renzulli, 2022). Phenocryst consists of plagioclase, hornblende, pyroxene, biotite, and opaque minerals.…”

Tracing the human movements of three thousand years ago by volcanic grinding tools in the Final Bronze Age settlement of Monte Croce Guardia (Arcevia-Marche Region, central Italy)

“…Literature data on the provenance of the lava millstones from the Protohistoric period to the Roman Empire are abundant. Most researches point out the italian volcanic areas of provenance 36 : the Roman Volcanic Province such as the Vulsini Volcanic Complex with a strongly exploited leucite phonolite quarrying site near Orvieto 17 , 37 – 39 and Vesuvius 40 , 41 ; Vulture Volcano 42 – 44 ; eastern Sicily volcanoes: Etna and Hyblaean Mountains 26 , 31 , 39 , 44 – 47 ; Sardinia volcanic province, mainly the Mulargia site 44 , 48 ; volcanic islands of the Sicilian Channel, mainly Pantelleria 23 , 49 or the southern Tyrrhenian Sea such as those of the Aeolian Archipelago and Ustica Island 46 , 50 , 51 ; volcanic islands of the Aegean Sea 15 , 30 , 44 , 52 , 53 . In addition, millstones found in shipwrecked cargoes contributed to exactly trace the trade networks from the volcano/volcanic area of provenance to the final destinations 23 , 30 , 36 , 54 .…”