Volcanic Pozzolan from the Phlegraean Fields in the Structural Mortars of the Roman Temple of Nora (Sardinia)

In this paper, we discuss the presence of volcanic pozzolans in structural mortars Roman Temple Nora Sardinia (3rd c. AD), represented by pyroclastic rocks (pumices and tuffs) employed as coarse fine aggregates. The provenance these materials from Phlegraean Fields was highlighted through a multi-analytical approach, involving Polarized Light Microscopy on thin sections (PLM), Scanning Electron with Energy Dispersive Spectroscopy (SEM-EDS), Quantitative Phase Analysis X-ray Powder Diffraction (QPA-XRPD), Fluorescence (XRF) investigations. These pozzolans, outcropping Bay Naples between Pozzuoli Vesuvius, are traditionally associated pulvis puteolana, famous pozzolanic ash prescribed Vitruvius Pliny order to confer strength waterproofing capabilities ancient concretes. This is first evidence trade material Neapolitan area Sardinia, starting at least Middle Imperial Age. use puteolana seems primarily targeted strengthen above-ground masonries, while were not strictly pursued. opens new questions about construction reasons for which demand commercialization product intended.