According to the archaeologists’ hypotheses, kilns were established in places where clay was widely available. The slaves who worked here would shape the handles first, stamp each one and then attach them to the body of the amphora: this is why we often find the imprints left by the potter’s fingers as he fixed the two handles to the vessel. The firing took place in the kiln over several days; the amphorae were then left to cool before the roof of the kiln was broken up and dismantled.
It is estimated that a 70 cubic-meter kiln could hold as many as one thousand amphorae arranged on seven or eight levels and that every firing required 50 tons of wood. On the site of Giancòla, located a little further south on the eastern side of a canal, which was navigable at the time and equipped with a docking structure, a large number of amphorae were found, bearing the seals of Apollonides, Archelia and Philippus, the names of the slaves who worked on the plants owned by Visellius in the first century BC. On what was once the production site we find two large rectangular and one circular-shaped furnace, with underground combustion chambers surmounted by a raised perforated floor and a large chamber where the amphorae were placed ahead of firing.
The kilns were covered by a heat-resistant vault which could be removed after each firing. The furnaces located in Marmorelle, also served by the Giancòla canal, were the property of Visellius as well. Here, in addition to numerous earthenware remains, four more rectangular kilns were uncovered.