Behind the town of Torano, on the territory that also englobes the fields of Colonnata and Miseglia, lies one of the most important quarries of the Luni region, the Zampone quarry, where – as Emanuele Repetti indicated – an excellent white statuary marble is quarried. Repetti carefully describes this site, situated in the Pianello valley and rightly called the Valley of Marble. This natural basin lies intermediate between the large calcareous rock of the overhanging mountains and the cavernous calcareous rock of the lower lands. In earlier epochs, the valley was occupied by a lake, traces of which remain in the water that stagnates here in winter, and in the name "Sponda" (bank) which this passage is still called. According to Lazzoni, the first utilisation of the marble field of Torano dates to the «60th year of the Christian Era».