A Mountain of Glass Foam
The northeastern coast of Lipari is dominated by a startling landscape: the brilliant white slopes of the former pumice quarries. This is what remains of Monte Pilato, a volcanic cone that has been systematically excavated for centuries, leaving a 200-meter-high rock face that looks like a marble cliff from a distance. The rock is pumice, an igneous stone formed during explosive volcanic eruptions.
Pumice is a foam of volcanic glass. It is created when super-heated, gas-rich magma is violently ejected from a volcano. The rapid decrease in pressure allows dissolved gases like water and carbon dioxide to expand and form bubbles, just like opening a carbonated beverage. This frothy magma then cools and solidifies almost instantly, trapping the gas pockets, or vesicles, within the rock. The composition of Lipari's pumice is rhyolitic, meaning it is high in silica (about 71%) and low in iron and magnesium oxides, which gives it its white color. This high porosity, which can be up to 90% by volume, results in a very low density—often less than that of water, allowing it to float. The last major pumice-forming eruption on Lipari occurred around 700 AD, blanketing parts of the island in a thick layer of this buoyant stone.
From Roman Tools to Industrial Ruins
Humans have exploited Lipari's volcanic geology for millennia, beginning with the obsidian trade in the Neolithic period. Pumice was also valuable. The Romans used it as a lightweight aggregate in concrete and as an abrasive for smoothing parchment. In the modern era, industrial-scale quarrying began, and for much of the 20th century, Lipari was a world leader in pumice production. The company Pumex S.p.A., founded in 1958, drove an industry that was central to the island's economy, exporting the white stone globally for use in construction and cosmetics.
The industry's success came at a high environmental cost. The quarrying reshaped the island's terrain and created significant dust pollution. After the Aeolian Islands were designated a UNESCO World Heritage site in 2000, pressure mounted to halt the mining operations. Despite local protests over job losses, the quarries were officially and permanently closed by police in August 2007. Today, the area is an abandoned industrial archeological site. The surreal white slopes are scarred by the remnants of mining infrastructure—iron piers, conveyor belts, and derelict factory buildings—left behind as if the workers walked away.