The Tuscan Sandstone from Firenzuola is a sedimenary rock of Marnoso‐arenacea formation, typical of Tuscany and Emilia‐Romagna, which forms the backbone of the northern Appenines. Tuscan Sandstone was formed thousands of years ago, in a deep sea, where periodic underwater landslides took place, moving primarily sandy sediments coming from erosions in the Alps that, even then, were beginning to rise due to the collision of the African and European tectonic plates. With the advance of the African tectonic plate, the sea was isolated and the deposited material that arose came to form the Appennine Mountain range. The particularity of the Marnoso‐arenacea formation, from which Tuscan Sandstone is extracted, and whose name derives from the presence of muscovite mica (silicate) shavings, which reflect light like miniature mirrors, is that it consists of 4‐meter to 5‐meter layers, each of which were formed during a single underwater landslide. The University of Bologna has given us scientific details:

• Kg/cm. 1156 unitary weight compression resistance

• high thermal resistance

The samples were subjected to 20 thermal alternations from ‐28˚C for three hours in air to +35˚C for three hours under water. At the end of the experiment there were neither signs of damage nor weight loss in the samples. The compression test provided the following average result: Kg/cm. 1045 unitary weight.