The site of Sennixeddu, situated 350 m west of Su Forru de is Sinzureddus, shows an extensive outcrop of obsidian, both in its natural form and as the product of flaking. Surveys in the area have shown that the zone covered by the obsidian includes the entire Sennixeddu canal, which from the spring of the same name runs west until it follows the edge of the site of Su Forru de is Sinzureddus. Sampling campaigns were carried out during 2002 in the western sector and in 2005 in the eastern one. The archaeological finds attest the material was worked using direct percussion, indirect percussion and percussion. On the basis of sporadic finds of a few bifacial foliates fragmented in antiquity it is thought that there had been a slow reduction in the material attributable to the late Neolithic. (MiBAC)