Pietra serena is a gray sandstone used extensively in Renaissance Florence for architectural details. It is also known as Macigno stone. The material obtained at Fiesole is considered the best and it is also quarried at Arezzo, Cortona and Volterra. 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.
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Pietra serena Wikipedia(Text) CC BY-SA