STUCCO. - It is a mixture of lime and pozzolana blended with marble dust or gypsum; once dried it becomes hard and workable with a chisel and gouge; the variety known as "scagliuola" is soft, malleable like clay, and sets with water: it can be worked with simple spatulas and even with molds and matrices. It was widely used since the most ancient times because of the relative ease of its working and application.
Egyptian architects and painters used it both for plastering interiors and for preparing the painting of wooden chests or sarcophagi and the masks of mummies. In Cretan art (Minoan Palace of Knossos, ca. 1600 B.C.) and in Etruscan art (Vulci, Tomb François, ca. 300 B.C.; Cerveteri, tomb of the stucchi) it was employed in plastic decoration with a technique analogous to that of bas-relief. No monuments survive from the classical and Alexandrian era. Examples of decoration from the Roman imperial age, monochrome or interspersed with various fields of color, or combined with those particular figurations that are called grotesques (v.), were brought back by archaeological excavations in entire schemes of the finest execution, especially at Pompeii (Stabian Baths, Tepidarium near the Forum, Temple of Isis), and at Rome (Palaces of the Palatine, Nero's Domus aurea, ambulatories of the Colosseum, etc.). The stylistically most important monuments are the stucchi of the so-called Villa Farnesina, now in the Museum of the Terme, those of the so-called underground Basilica of Porta Maggiore (both of the Augustan age) and of the suburban tombs of the Valerii and the Pancratii.
In the early Christian era, after the examples of the tombs of St. Sebastian (hypogea of the first half of the 3rd century A.D.), the most distinguished monument that still presents its decoration intact, in the succession of marble inlays, stucco and mosaic, is the Baptistery of the Orthodox at Ravenna (5th century). Although still effective in their overall effects, these stucchi reveal in their details the uncertainty of the technique.
In the barbarian era and during the Romanesque and Gothic periods, the use of stucco was rarer (churches of Disentis in Switzerland, of Malles in Alto Adige, of S. Maria in Valle at Cividale, of Genzode and of S. Maria of Halberstadt in Germany). In these centuries, especially in the exterior decoration of civil buildings, various terracotta varieties improperly called stucco were preferred. In the Renaissance the taste for plastic stucco revived. In the ceiling and at the top of the wall in the hall of Palazzo Schifanoia at Ferrara, Domenico di Paris modelled with the subtlety of a ingenious goldsmith an unsurpassed series of motifs with festoons, medallions, fruits, allegorical figurations of virtues, etc. But the material employed in the 15th century, resulting from various combinations of gypsum, lime, Greek pitch, wax and brick dust, treated by fire (Vasari), could not compete with the ductile quality of Roman stucco. It was Giovanni da Udine, around 1516, who rediscovered the formula of the ancient combination, mixing clear marble dust with lime of white travertine, and gave the start to the golden age of stucco decoration. In the courtyard of Palazzo Massimo alle Colonne, in the Logge of Raphael, in Palazzo dell'Aquila, at Villa Madama, at the Farnesina in Rome; then in Palazzo Vecchio and in the New Sacristy of S. Lorenzo in Florence, as at Venice, Padua, Udine, he left examples that were widely imitated throughout the 16th century. A host of artists, from Daniele da Volterra, to Perin del Vaga, to Lucio and Giulio Romano, to Felice Brandani, to Alessandro Vittoria, extended throughout the peninsula the use of this decoration, which gradually evolved, from the barely projecting and most elegant line of the first manner dominated by Raphaelesque influence, toward more complex and heavier combinations.
Seventeenth-century stucco rivalled sculpture in the pursuit of plastic effects. In its execution Lombard artists distinguished themselves: Prospero Bresciano worked in the Vatican, G. Ferabosco and S. Castelli were active in Rome; B. Bernasconi, C. De Marchi in Genoa; G. A. Sala in Bergamo, Venice, Bologna, Florence. Around Maderno, Bernini, and P. da Cortona gathered a group of Roman stucco-workers among whom Cosimo and Giacomo Fancelli and Antonio Raggi emerged. The masterpiece of seventeenth-century decoration in Rome is perhaps the Palazzo Mattei.
At Turin, in the Castello del Valentino, the Campione artists Francesco and Pompeo Bianchi worked, for whom their father Isidoro supplied the designs. Toward the end of the century, above all rose, for the genius of his inventions, the Palermo-born G. Serpotta (v.). During the eighteenth century, in interpreting the refined and sometimes exoticizing taste of gallant society, the Venetians achieved primacy. The magnificent villas scattered through the Venetian hinterland were enriched with splendid decorations. In the wake of Tiepolo, Venetian stucco-workers conquered Milan and Lombardy. In Sicily the example of Serpotta kept a flourishing school alive. The neoclassical style was inaugurated by Giocondo Albertolli, animator, in northern Italy, toward the end of the 18th century, of a nursery of stucco-workers, much sought after everywhere. During the nineteenth century the art of stucco declined, especially in the often coarse use, aimed at effects of false relief, of that flowering of neo-styles, which lacked all imagination and sensitivity. In the most recent era, and particularly after the Second World War, it has instead returned to great fortune, especially in the decoration of public halls (auditoriums, cinemas, etc.). Stucco is also employed for certain color effects in theatrical and cinematic scenography, sometimes with positive results. - See pl. CIII.
