In comparison with the other mines of the lglesiente, Orbai ranks as minor, as it never acquired the same renown as others such as Rosas and Monteponi.
Situated not far from the town of Villamassargia, near the banks of the river Cixerri, this lead and zinc mine began production around 1872 when the mining concession was awarded to the Societa degli Orbi from which it took its name. However, the con­cession holders, some of whom were also owners of the land, failed to factor in the ore transport difficulties caused by the lack of road links to the loading ports. Cooperation agreements with the nearby mine of Rosas and its manager, engineer Um­berto Cappa, yielded scant benefits, in view of these operating difficulties. So in 1893 the mine was handed over to the English company United Mines Ltd which improved equipment and ma­chinery and rationalised work. Their stay lasted only 14 years and in 1907 the /ta/a-French company Pertusola took over own­ership and management until the early 1940s. Shortly after, on the initiative of the Montepon i mining company and its manager, engineer Enrico Musio, prospecting was once again begun to obtain a better idea the deposit's potential, and produced fairly good results. Thus after the end of the war, in agreement with Monteponi, mining works were re-started under the name of the Societa delta Miniera di Orbai: unfortunately, performance was once again unsatisfactory and after a few years (in the 1950s) the mine was closed and the concession withdrawn.