Spectroscopic, microchemical and petrographic analyses of plasters from ancient buildings in Lamezia Terme (Calabria, Southern Italy) Raffaella De Luca ⁎, Valentina Gigliotti, Mario Panarello, Andrea Bloise, Gino M. Crisci, Domenico Miriello Department of Biology, Ecology and Earth Sciences, University of Calabria, Via P. Bucci, Cubo 12B, 87036 Arcavacata di Rende (CS), Italy abstract article info Article history: Received 7 May 2015 Received in revised form 26 June 2015 Accepted 11 August 2015 Available online 13 August 2015 Keywords: Archaeometry Pigments Spathic calcite Gold Raman spectroscopy SEM–EDS microanalysis This work shows the results of the spectroscopic, microchemical and petrographic study carried out on six plas- ters coming from three important residential buildings of the 18th century, located in Lamezia Terme (Catanzaro, Southern Italy). To study the provenance of the raw materials used to make the plasters, one sample of limestone and two samples of sand were also collected from the quarries near Lamezia Terme and compared with the his- torical plasters. Samples were studied by polarized optical microscopy (OM), X-ray powder diffraction (XRPD), scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS) and Raman spectroscopy. The results of these analyses allowed to determine the mineralogical, petrographical and chemical characteristics of the plas- ters, identify the pigments used for their coloration and provide useful information about the building tech- niques, the raw materials employed and the production technology of plasters during the 18th century in Lamezia Terme. SEM–EDS microanalysis also revealed the presence of gold and silver on the surface of two samples. © 2015 Elsevier B.V. All rights reserved. 1. Introduction The city of Lamezia Terme is located on a floodplain in the south of Italy, in the middle of the Calabria region (Fig. 1a), it comes from the union of the three municipalities: Nicastro, Sambiase and Sant' Eufemia. In this city, the residential buildings of the 18th century have a huge artistic-architectural importance because they represent a particular ex- pression of the baroque and rococo styles. At that period, important plasterers, often specialized out of the territory, were engaged in the re- alization of decorations for the facades of some churches. At the same time, the upper classes of the city commissioned, at these plasterers, elaborated decorations for their buildings to declare their social prestige. The buildings of this period are characterized by decorations with sophisticated symbolic meanings and allegories designed to celebrate the importance and the strength of families, often directly involved in the projects [1]. Facades are marked by a succession of balconies with iron “goose breast” railings. The portal is decorated with the family crest and phytomorphic and zoomorphic elements. It is often flanked by pilasters and overtopped by balconies which are framed by decora- tive plasters that make them look like sumptuous mirrors. In this work three residential buildings of the 18th century were studied. Palazzo Statti (Fig. 1c), in Nicastro, is characterized by a dense decoration on the upper band and on the corner, it presents also con- cave and convex surfaces that, alternate each other, giving to the facade the appearance of a parchment [2]. Palazzo Nicotera, in Sambiase, shows a particular decoration of the balconies (Fig. 1d). The birds in the middle are probably phoenixes, birds that can rise from their ash [3] and the decorations on the sides seem to be flames. The main facade of Palazzo Cerra, in Sambiase, is embellished with different decorative effects (Fig. 1e); the balconies show little heads in the middle and also the lodge in the courtyard presents rich decorations. From these three buildings six samples of plaster were collected. The term “plaster” indicates an artificial stone material, composed of a mixture of lime, aggregates and water, used to finish the surface of a wall. In addition, to study the provenance of the raw materials, geological samples of sand and limestone were also collected from the quarries near Lamezia Terme (Fig. 1b) and compared with the historical plasters. The samples were characterized with the aim of obtaining information on their production technique, the provenance of the raw materials and the constructive history of the buildings. Indeed the characteriza- tion of plasters and mortars can provide important archaeometric infor- mation on historical and archeological monument, identifying their constructive phases, the technological process involved in their Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 153 (2016) 184–193 ⁎ Corresponding author. E-mail address: raffaella.deluca@unical.it (R. De Luca). http://dx.doi.org/10.1016/j.saa.2015.08.018 1386-1425/© 2015 Elsevier B.V. All rights reserved. Contents lists available at ScienceDirect Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy journal homepage: www.elsevier.com/locate/saa