The building materials of the Theatre of Marcellus, reflect Roman builders' careful selections of tuff and travertine for dimension stone and volcanic aggregates for pozzolanic concretes. The vitric-lithic-crystal Tufo Lionato tuff dimension stone contains a high proportion of lava lithic fragments, which increase its compressive strength and decrease water sorption, enhancing durability. Sophisticated installations of travertine dimension stone reinforce the tuff masonry, which is integrated with durable concrete walls and barrel vaults. The pozzolanic mortars of the concretes contain harenae fossiciae mainly from the intermediate alteration facies of the mid-Pleistocene, scoriaceous Pozzolane Rosse pyroclastic flow. They have pervasive interpenetrating pozzolanic cements, including strätlingite, similar to highquality, imperial era mortars. Concrete walls are faced with refined Tufo Lionato opus reticulatum and tufelli, and opus testaceum of fired, greyish-yellow brick. The exploratory concrete masonry, which includes some of the earliest examples of brick facings and strätlingite cements in Rome, and the integration of these materials in complex architectural elements and internal spaces, reflect the highly skilled workmanship, rigorous work-site management and technical supervision of Roman builders trained in republican era methods and materials.

Small quantities of Roman mortars and stuccos from the Theatre of Marcellus and Porticus of Octavia were subjected to different instrumental techniques - thermogravimetric analysis (TG, DTG), Inductively Coupled Plasma Emission Spectroscopy ( ICP-AES) and X-ray diffraction (XRD). The instrumental characterisation and chemometries allowed the stucco samples to be easily distinguished from the mortar. In practice, using the three instrumental analytical methods a total of 36 variables were obtained. The variables were then selected using PCA ( Principal Component Analysis), reducing this number to 10. Lastly, using HCA ( Hierarchical Cluster Analysis) a good separation was obtained between the two groups of samples ( mortars and stuccos)

No abstract

Résumé Des juifs de Libye, obligés de fuir le pays en 1967 à la suite du déclenchement de la guerre des Six Jours se sont installés à Rome, « patrie » de la millénaire communauté juive romaine. Dans la « rencontre-accrochage » de ces deux groupes, l’entrelacement entre composition des mémoires et recomposition des identités sur le plan public devient particulièrement intéressant.