Filippo Brunelleschi, the Pazzi Chapel in Santa Croce, Florence

The building gives us insight into the ambitions of Renaissance architects in their struggle to bring coherence to the architectural language of columns, pilasters, arches and vaults. Between the pilasters in the transept there are tall, blank, round headed panels and, above them, roundels, common Renaissance decorative motifs. The architectural elements of the interior are all in pietra serena, a high quality, fine grained sandstone.°

Mary McCarthy:

«The interior is a simple rectangle with four high narrow windows and bare white walls and at the end a small apse. In the four corners tall closed arches are drawn in dark-grey pietra serena on the white walls, like the memory of windows. Fluted pilasters with Corinthian capitals, also in pietra, are spaced along the walls, marking the points of support, and in the same way, the lunettes and supporting arches of the chapel are outlined in dark ribbons of stone against the white plaster, and the binding arches have stone rosettes enclosed in rectangles drawn on the white background. Arch repeats arch; curve repeats curve; rosette repeats rosette. The rectangles of the lower section are topped by the semi-circles of the lunettes and arches, which, in turn, are topped by the hemisphere of the cupola. The continual play of these basic forms and their variations – of square against round, deep against flat – is like the greatest music: the music of the universe heard in a small space.»[6]

Pietra serena

Pietra serena is a gray sandstone used extensively in Renaissance Florence for architectural details.[2] It is also known as Macigno stone.[3] The material obtained at Fiesole is considered the best and it is also quarried at Arezzo, Cortona, and Volterra. [3]

Examples of its use in Florence include the interior pilasters, entablatures, and other decorative elements of Brunelleschi's Pazzi Chapel and Michelangelo's Medici Chapel.

Physical traits

Pietra serena comes out of the ground as a blue-gray color. Due to a chemical reaction in the stone, it turns into red. This is due to oxidization in the clay matrix of the stone. Pietra serena has a very limited durability. This has led to problems with conservation efforts. This durability is also the reason why it is very workable.[4]

Quarries

Pietra serena was very popular in the Renaissance, and because of this the quarries where the stone was found were exploited. Depending on the quarry, the grain size of the stone varies. Trassinaia was the main quarry used in the construction of Brunelleschi's Pazzi Chapel.[5]