Pietra Serena


Braschi quarry

Year designation



Sandstone; Lithic Arkose containing quartz, feldspar lithic clasts, muscovite, biotite, chlorite with varying amounts of clay matrix and calcite cement


Bluish Green / cerulean and ochraceous

Geological settings

Cenozoic – Upper Oligocene/Lower Miocene – Macigno and Monte Modino Formation


Northern Apennines, region of Firenze

Braschi quarry

The stone of the Renaissance

Pietra Serena is a material that can be utilized for architectural elements, ornaments, road paving, household furnishings, and even religious and civil objects. The cyclopean blocks of the Etruscan walls of Fiesole (Florence) evidence that Pietra Serena was put to use in the Archaic period. Since that time its use lasted almost continuously until the 19th century. The most frequently used material in Florentine Renaissance architecture (UNESCO World Heritage) was Pietra Serena, a sandstone that nowadays is found in a quite satisfactory state of conservation. The reason for this is that architects and stone cutters in the past made careful selections of the materials they employed. For centuries, the sandstone outcrops have provided the building material for the city. The particular colour of the city is due to the use of these sandstones: ochraceous shades for the aristocratic palaces, the public administration buildings and civil houses (Pietraforte), and cerulean colours for the large colonnades and the paved streets (Pietra Serena). Pietraforte was the primary building material of the city, while Pietra Serena was used chiefly for ornamental purposes, having its most exalted period during the Renaissance when large blocks of this sandstone were required to carve columns and capitals. Today, the depletion of many quarries and the consequent high cost of the stone, have determined the use of the Pietra di Firenzuola (Cantisani et al. 2013) and Pietra di Santa Brigida (both quite similar to Pietra Serena) where it is required by the historical stylistic context.

Spedale degli Innocenti, Florence, Italy

Fabio Fratini