The salt works are composed of numerous evaporation ponds linked by sluice gates. The basins could be divided in two different sectors: evaporating pans, where the solution is concentrated, and salting tanks, where occurs the precipitation of the salt. The seawater, called “virgin water”, is taken from the sea using water pumps and moved to the first tank. At beginning , the concentration of salt is around 3,5 Baumé (°Bé) which increases till to reach 11° Bé where start to occur the first precipitation, among which the most evident is the calcium carbonate. In the following pan it reaches the 20° Bé in which the calcium sulphate precipitates, and finally it reaches in the last evaporating tanks the concentration of 25,7à Bé where “virgin water” loses all its impurities.
At the end of the process, under the name of “mother water”, the water, moved to the salting tanks, is saturated of salt which is deposited in the bottom. Here the salt concentration reaches the 30° Bé. Above this concentration, the “mother waters” are pour into the sea or otherwise into other basins to extract other salts.In the bottom of the tanks, the salt forms a concretion of 10-20 cm which needs to be broken and collected in order to transport, paying attention to not pollute it with the bottom of the basins. The harvest is from April to September.
In the basins, water can assume a reddish colour due to the presence of a particular micro-algae: the Dunaliella salina, able to live in these saline environments, which gives a colour ranging from pale pink to brick red depending on its density.