The “Val d’Aran” is a valley situated on the Atlantic sideof the Pyrenees. Located in the northwest corner of Cat-alonia, has easy connection with France by the course ofthe Garonne River, which forms the main communica-tion route, flows over land Aquitaine and empties intothe Atlantic Ocean near Bordeaux. Under Roman con-trol, the Aran Valley was part of the Novempopulaniaprovince.Five of the most significant archaeological artefactsfound in the Valley have been analyzed to investigatethe provenance of the marble used for their manufac-ture. These archaeological pieces dated from 2ndto 5thcentury AD, are currently deposited in the “Musèu deraVal d’Aran”. A combination of techniques with OpticalMicroscopy, Cathodoluminescence (CL) and Isotope-Ratio Mass Spectrometry was applied to know theirmarble source.To carry out the comparative study with quarry mar-bles, local outcrops were examined and sampled. Mar-bles from the quarry of Arties were specially taken intoaccount since, at least from the medieval times, wereused with building purposes. The nearby Roman quar-ries of Saint-Béat have also been taken into considera-tion. The analytical results after applying the samemethodology to both marble samples, artefacts andquarries, allow differentiating the two marble sources,Arties and Saint-Béa