The exploitation of the quarries of portoro had such a development that in 1862 were surveyed as many as thirty. One of the most efficient quarries was the Cava Merlini on the island of Palmaria (1908) which occupied many quarrymen, some locals, others from Carrara. The work was very hard and very dangerous, the sectioning of the marble block was carried out with helical wire (900-1000 meters long) operated by an electric motor located at the bottom. In Porto Venere it is still remembered the landslide of 100 tons occurred in the quarry of the Crocetta, where the gate was…