It was designed by Cosimo I, but its implementation is due to his successor Ferdinand I, who commissioned the architect Matteo Nigetti 1604 to a design by Don Giovanni de 'Medici, brother of the Grand Duke. The same Buontalenti intervened by changing part of the project. Mosaic of the emblem of Florence, the Chapel of the Princes. The dazzling splendor is given by the rich Florentine mosaic inlay, for the realization of which was created the Precious stones. This art, which is still practiced mainly in the decoration of furniture and vases, found here its peak, although the funereal tone of the work made him choose the colors more muted and dark with porphyry and granite.