Perdu Spada

Perdu Spada (often cited as Mitza de Perdu Spada) is one of the small warm springs found along the margins of the Giba plain in the Sulcis, in a rural setting shaped by a fault system trending E–W to NW/SE.
Using your material: it belongs to a group of six “thermal” springs in the area (with Perdu Mannu, Peppi Marroccu, Acqua Callenti, Fonte Calda, and Campu Pisanu). The waters are bicarbonate–alkaline–earth, with temperatures generally between 23°C and 30°C, pH ~6.7–6.9, and modest flows (roughly 0.4–1.5 L/s, depending on the spring).

Online references also describe Mitza de Perdu Spada as reaching about 30°C and being among the warmest springs in the Basso Sulcis, often associated with the Narcao area.

The exact location of the spring might me near the Nuraghe Spada.