Salt production in Italy: from ancient salt springs to modern mining

In Italy, salt production methods evolved over the centuries, from coastal salt pans to artificial evaporation of brines, to modern underground and solution mining. Rock salt production in inland areas dates back to Etruscan times, in modern Tuscany. In the Middle Ages, the salt springs of Volterra were systematically and continuously exploited, and since the early 1900s production was carried out with engineered solution mining, that allowed Solvay to build a large soda factory in Rosignano in 1913. In the last decades of the 20th century, solution mining started also in Calabria. Here, in the Timpa del Salto mine, some sinkholes appeared in 1984, triggering a landslide and an overflow of brine, an event that gradually led to the interruption of mining activities. Calabria is also known for the longest-lived Italian underground rock salt mine (Altomonte-Lungro mine), exploited almost continuously since antiquity and active until 1978. Finally, in Sicily, numerous underground salt mines were intensively exploited since the second half of the 20th century, and three are still active (Realmonte, Racalmuto, Petralia). We outline the historical development of these Italian salt production sites and the evolution of mining technologies as used in different geological contexts.