The origin of the ore body of Sulphur of Perticara is connected to the evaporitical conditions which began 6 millions of years ago, in the Messinian era. Thanks to the closing of the Straits of Gibraltar and to the intense evaporation of the sea water, there was a progressive increase of the saline concentration that brought to a selective precipitation which started from less soluble terms and ended with the ones more soluble. This crisis of salinity of the Mediterranean Sea favored the precipitation of calcium sulfate (CaSO4) and the formation of sediments called “gypeseous-sulphur bearing formation”. The presence of sulphur could be connected to a bacterium’s action, that in basins with a low level of circulation, could manage to extract sulphur from waters containing both H2S and SO4; or though the reduction of chalk and sulphates, after the sedimentation, which took place exclusively in a fluid environment, in presence of bituminous substances or/and hydrocarbons.

The sulphur ore body of Perticara has a surface of about 5 square kilometers in an area delimitated by three faults and it consists of 13 gypeseous layers, but just the last 5 layers are in part mineralized. 4 of them have a thickness of about 2 meters, while the other one is more consistent and it’s called master layer because it has a thickness of 22 meters in the center and of 14 meters in the edges. The level of mineral in some portions of the ore body could reach the 40%. The mine of Perticara was characterized by a huge amount of bitumen, but also by findings of wonderful crystallizations which enrich the most important collections and museums of the world. In the mine of Perticara has been extracted the biggest crystal of sulphur of the world, which was donated in 1936 by the engineering Elvino Mezzena to the Civic museum of the natural history of Milan where it’s still kept.

The incessant work of miners led to the construction of a huge underground city, that today is hided under the village of Perticara. Centuries of exploitations of the ore body led to the realization of about 100 kilometers of galleries, inclined shafts and slants, set on 9 levels. Miners could go down to 60 meters under the sea level, more than 700 meters underground. The cultivation of mineral has been made using different techniques: from the big cages to the pillars, using also the reversed step which needed the sending of gobs underground in order to fill some empties. The wideness of the underground , connected to the necessity of sorting an important traffic of miners toward yards of production joined with sulphur rocks directed outside, together with the importance of airing kilometers and kilometers of galleries in order to allow to the fresh air to arrive underground and in order to make toxic gas flowing outside, made the construction of several accesses indispensable. At the beginning there were Croce, Alessandro, Paolo and Montecchio wells and the Fanante inclined shaft, then Vittoria, Perticara, Parisio and Mezzena wells were built, together with Monte Pincio, Savignano and Tornano inclined shafts. All these structures allow the normal functioning of the underground work.