Petrographic characterization of an opus sectile found in the Roman town of Pollentia (Alcudia, Majorca, Spain)

Abstract

This paper presents the preliminary results of the petrographic characterisation of the stones used in an opus sectile pavement discovered at Pollentia (Alcudia, Majorca, Spain). The importance of this element basically lies on its relation with a large building in the area of the Forum and the fact that it is the first one of its kind to be found in recent excavations at this Roman town. The materials are white limestones and black/grey lutites. In order to identify the provenance of these materials, the same island of Majorca and the nearby island of Minorca were the first to be considered. Indeed, white limestones are abundant at Majorca, while the nearby Minorca presents a higher number of Paleozoic outcrops that could be considered as potential sources for the black/grey materials. Thus, the first step consisted on the analysis and comparison of the Paleozoic stones used at the opus sectile and those from Minorca’s outcrops. Some samples from a Roman site at Minorca were also included on this analysis due to their potential similarity to the samples from Pollentia. On the other side, the provenance of the white limestones is still on its earlier stages and in progress. Nevertheless, the bibliographic references on the Majorca geology and the first characterization (macroscopical and microscopical) of the white limestone strongly point at a local origin; thus providing the basis for the next step (survey, location and sampling of the outcrops) of the further research that we will undertake.