Exploitation of mother of pearl in the Middle Ages, Clos d'Ugnac archaeological site (Pennautier, Aude, France): Malacological study, consumption, exploitation and utilization of the nacre

The archaeological site of the Clos d'Ugnac (Pennautier, Aude, France) was the object of an archaeological prescription by the Regional Service of Archaeology (SRA), of an archaeological diagnosis in 2012 and a preventive excavation in 2013, due to a housing development. The excavation showed an occupation from the Neolithic to the late Middle Ages. The main occupation is dated from the Middle Ages, between the 9th and the 14th century, and extends over the whole footprint, 18 000 m2. The numerous structures included paths, buildings, crafts, and agrarian structures (pits and silos), two graves, and plots of land. The current study demonstrated the working of mother of pearl, thanks to the examination of the valves of Unio mancus/pictorum, from the choice of the raw material to the shaping. This study involves a handmade specialty which is not perceived through a finished article, but through an operating chain required by this material. It is possible to bring to light this type of activity by studying the aspect of the valves of mollusks. This type of activity is rarely perceived on archaeological sites.