Pietra serena

[2] The material obtained at Fiesole is considered the best and is also quarried at Arezzo, Cortona, and Volterra,[2] although it is no longer being actively mined and has been placed under conservation status due to depleting resources.

[4] Pietra serena was first largely discovered by the Etruscans in the Archaic period who occupied the medieval Italian area of Fiesole.

It was used in the construction of much notable Italian architecture during the "Golden Age of Rome", including that of artists such as Michelangelo, Donatello, Brunelleschi, and Vasari.

[4] The use of pietra serena by such well-known Italian figures in the art world then promoted it to a wider market,[5] and it became a more popular material for aesthetic and architectural purposes, and also amassed "social and economic importance".

[4] The quarries are located in the city of Florence itself, making it inexpensive and easily accessible to mine for pietra serena during the height of its extraction in the Renaissance period.

A study of the quarries in the Florentine area found that "In spite of almost uniform features, various beds have different operating performances due to the small distinction in the percentage of calcite and clay, as well as in the grain structure".

[4] Specific identifications have been attached to each sub-type and the quarry they hail from according to the differences in their make-up, and "In the Fiesole area, these discontinuities have traditional denominations: the bedding is known as falda, while the joint sets are referred to as mozzatura... and recisa.

[4] After extraction from underground, the clay matrix of the stone undergoes oxidisation and gives the material a more red-brown colour, although it partially maintains its blue tone.

Concerns for depleting natural resources within the quarries led to them being left alone and for conservation efforts to increase in the twentieth century, mainly through reforestation.