The salt evidence
During the excavations, salt-production evidence was found in two soundings (F and G) and in many different places around the northern island, in the shallow water. In sounding F, many so-called pedestals were unearthed inside a domestic context belonging to Middle Bronze Age (sub-phases 1/2).
The pedestals are usually found in European briquetage contexts. The briquetage is a technique which has been widely used in Europe to extract salt from brine, by boiling the latter over disposal ceramic vessels. The vessels had to be broken to extract the salt cake, thus forming large accumulations of dump potsherds, all belonging to almost the same type of container.
To test the hypothesis, we perform some chemical analyses in collaboration with the Earth Science Department of the University of Rome La Sapienza (G. Sottili). In one of the analysed potsherd, we found salt crystals with amorphous and cubic plus octahedron shapes in some microcracks. These shapes of the crystals only formed when the supersaturated salt solution undergoes a very rapid cooling rate (not from usual evaporation), thus fitting very well the hypothesis of a deliberate vessel breakage after the cooking phase.
An alternative hypothesis might be the production of a fish sauce, similar to the later roman liquamen, whose recipe can be found in the X century agronomy books Geoponica (which may derive from a VI century CE Latin source). According to Geoponica, a mixture of fish, oregano and brine are boiled in a container to obtain the liquamen. When the mixture is cooked, the sauce is poured in other containers, thus the slower cooling rate of the salty sauce happens outside the first vessel.
In sounding G, a deposit made almost exclusively of half-conical potsherds have been excavated. The shape of the container and the absence of the usual ceramic set of a typical household points to a specialised context, which may be related to the salt production as well. The deposit can be dated to the Middle Bronze Age sub-phase 3, thus a little later than the context in sounding.
Both deposits, in sounding F and G, would represent the oldest strong evidence of ancient salt production in Italy.
If the salt hypothesis were to be true, the changing environments in which the productions took place (domestic to specialised area) might be connected to a socio-economic development already suggested by other evidence. Indeed, in the Middle Bronze Age 3, the first traces of an emerging elite can be found in central Italy, like the changing habits in funerary rituals, the presence of well-fortified settlements and, later on, the first potsherds of Mycenaean wares. Ruling a “marginal” activity like the salt-production may have been used by the emerging elite both to attract clientes, in a typical patron/client relationship, and to accumulate wealth.