Please cite this article in press as: R. Piovesan, et al., Stones of the fac ¸ ade of the Sarno Baths, Pompeii: A mindful construction choice, Journal of Cultural Heritage (2019), https://doi.org/10.1016/j.culher.2019.04.010 ARTICLE IN PRESS G Model CULHER-3583; No. of Pages 10 Journal of Cultural Heritage xxx (2019) xxx–xxx Available online at ScienceDirect www.sciencedirect.com Pompeii special issue Stones of the fac ¸ ade of the Sarno Baths, Pompeii: A mindful construction choice Rebecca Piovesan a , Lara Maritan b,∗ , Giulia Meneghin b , Caterina Previato c , Siwar Baklouti d , Raffaele Sassi b , Claudio Mazzoli b a Piovesan Consulting, via Venozzi 28/E, 31040 Volpago del Montello, Italy b Department of Geosciences, University of Padova, via G. Gradenigo 6, 35131 Padova, Italy c Department of Cultural Heritage: Archaeology, History of Art, Cinema and Music, University of Padova, piazza Capitaniato 7, 35139 Padova, Italy d Département de Géologie, Faculté des Sciences de Tunis, Université Tunis El Manar, Tunis, Tunisia a r t i c l e i n f o Article history: Received 23 July 2018 Received in revised form 4 March 2019 Accepted 19 April 2019 Available online xxx Keywords: Lithological mapping Pompeii Campanian Ignimbrite Somma Vesuvius lavas a b s t r a c t The lithological analysis of the southern fac ¸ ade of the Sarno Baths, a complex building located in the south-western part of the ancient city of Pompeii (Naples, southern Italy), was addressed to define the types of stone used as blocks and ashlars of the three nearly completely preserved levels. Lithological analysis, coupled with petrographic (optical and electron microscopy) and mineralogical study of the lithotypes macroscopically defined, revealed the use mainly of volcanic and volcano-clastic rocks, and in particular of: (i) yellow tuff supplied from the yellow facies of the Campanian Ignimbrite (about 39 ky BP); (ii) grey tuff from the Campanian Ignimbrite; (iii) leucite phonolitic tephrite from the lava flows of Somma Vesuvius; (iv) travertine from the Sarno limestone (Calcare del Sarno) (Cretaceous). On the basis of the lithological mapping, the basement results mainly composed of leucite phonolitic tephrite, associated to travertine and sporadically to yellow tuff, whereas the other two overhead levels are mainly constituted by tuff and travertine, respectively. In particular, the tuff distribution on the level upon the basement shows a prevalence of grey tuff on the western portion, yellow tuff on the eastern one and in the opus reticulatum band running all along the fac ¸ ade, and marked at the top by a trachyte stringcourse. Travertine blocks in the uppermost fac ¸ ade were probably placed as integration during the restoration works carried out at the end of the 19th century. The distribution on the fac ¸ ade of elements made of different rock types, characterised by different bulk density and mechanical properties, confirms ancient Roman builders’ deep knowledge on the technical features of these materials and their structural behaviour. © 2019 Elsevier Masson SAS. All rights reserved. 1. Introduction Global or partial lithological mapping of ancient buildings, espe- cially fac ¸ ades, represents an important tool for studying building phases and defining the lithological choices of ancient architects in different construction contexts and historical periods. When the use of different rock types is attested within the same construc- tion element (such as basement, walls, fac ¸ ades, floors), lithological mapping results particularly useful to properly describe rock types distribution (e.g. among specific parts of a monument, such as ∗ Corresponding author. E-mail addresses: rebecca.piovesan@gmail.com (R. Piovesan), lara.maritan@unipd.it (L. Maritan), giulia.meneghin@studenti.unipd.it (G. Meneghin), caterina.previato@unipd.it (C. Previato), siwarbaklouti11@gmail.com (S. Baklouti), raffaele.sassi@unipd.it (R. Sassi), claudio.mazzoli@unipd.it (C. Mazzoli). arches, columns, architraves, doorsteps, pillars, levels). This anal- ysis may also provide information on awareness of physical and mechanical properties of rocks, on availability of stone supplying from geological sources, on the construction or restoration phases in antiquity, and on aesthetic choices [1–9]. Lithological distribu- tion is the base map on which adding further information about deterioration patterns and products due to weathering before plan- ning possible conservation actions [10–20]. The southern fac ¸ ade of the Sarno Baths in Pompeii (Naples, southern Italy), with its complexity due to the superposition of dif- ferent building phases and construction techniques, represents an excellent case study to understand all the advantages of a litho- logical mapping. The fac ¸ ade, characterised by a length of about 40 meters and a height of 20 meters, arises along the southern slopes of the ancient city. The upper part is characterised by the presence of 11 windows which light the rooms situated at level -3 (from the walking level of Pompeii city), partly occupied by a thermal com- https://doi.org/10.1016/j.culher.2019.04.010 1296-2074/© 2019 Elsevier Masson SAS. All rights reserved.