THE TUNGSTEN AND TIN SIGNATURE OF IRON ORES FROM ELBA ISLAND (ITALY): A TOOL FOR PROVENANCE STUDIES OF IRON PRODUCTION IN THE MEDITERRANEAN REGION

The mineralogy, petrography and major- and trace-element composition of iron ores from Elba Island (Tuscany, Italy), one of the most important iron sources in the Mediterranean area since the first millennium bc, revealed that hematite-rich ores display prominent enrichments in W and Sn (up to 4950gg1 and 8400gg1, respectively). These two elements are hosted by tiny grains of WSn mineral phases (ferberite, scheelite and cassiterite) that are disseminated throughout the hematite matrix. A comparison with iron ores from many Italian and European localities (most of which were exploited in ancient times) suggests the uniqueness of the geochemical pattern of Elba Island hematite-rich ores (i.e., high W and Sn, low Mo and low Cu, Pb and Zn). We suggest that this geochemical signature may represent a new provenance marker not only for discarded ore at smelting/smithing sites, but, possibly, also for metallurgical slag and smelted metal produced in the chaine operatoire of the iron process.