CRYSTAL in ART. — Rock crystal (transparent, colorless quartz) has been known since antiquity as a material for fashioning small objects. Figurative or carved rock crystal objects with profane subjects are often found in the Paleo-Christian period in the Roman catacombs (Vatican, Profane and Christian Museum). Two unusually large lion heads, probably created for the decoration of a piece of furniture, are now preserved in the Cluny Museum in Paris. Unadorned pieces of crystal were used in barbarian earrings and thus in Merovingian art. Objects of crystal with religious iconography are extremely rare; for example, a fish (Vienna, Museum) and a carving of the *Adoration of the Magi* (Vatican, Sacred Museum).
In the early Middle Ages, the use of crystal became more frequent for both religious and secular objects.
Some Carolingian carvings replicate classical forms, even in technique. Notable is the seal of King Lothar on the cross of Aachen, formed by a disk depicting the story of Susanna (London, British Museum), which may have been worked in Metz. However, the vast majority of medieval crystal objects are of Eastern origin. Many were brought to Europe during the Crusades (such as those in the Treasury of St. Mark’s in Venice). Indeed, in almost all major treasuries, besides Venice, Aachen, Essen, Quedlinburg, Bamberg, Capua, and in the museums of Paris, London, and Nuremberg, these Eastern works are found; generally, they are goblets, cups, ampoules, plates, caskets, or pendants. The name of the Egyptian caliph appearing on a ewer in Venice and on a lunula in Nuremberg demonstrates that these crystals are largely Egyptian works of the 10th–11th century. Another group of tall, plain vessels without decoration were likely produced at the Norman court in Palermo and show the influence of Fatimid art.
Another center for crystal work developed in Venice. Characteristic of this school is filigree decoration, as seen in the candelabra of Charles II of Anjou (Bari, Cathedral) or in a reliquary from St. Gall in Rome (Vatican, Christian Museum). In Venice, however, smooth pieces of crystal were also used to protect relics; thus in the ancient reliquary of the Volto Santo in Rome (Treasury of St. Peter’s), donated by two Venetians in the year 1350. Sometimes crystals were placed over miniatures to protect them and lend them the brilliance of enamels, as in the triptych of Alba Fucense (Rome, Palazzo Venezia), or they were set at the center of large crosses (Assisi, Atri, Pisa).
In northern Europe, too, crosses, reliquaries, and pitchers of crystal were produced in the Middle Ages; a document from 1260 found in Paris alludes to this, while some fine crystal pitchers appear to have been made at the court of Burgundy.
At the beginning of the 16th century, a school for crystal work flourished in northern Italy. Very famous is the *Head of Lucretia* in Vienna (Lederer Collection), attributed to Tullio Lombardi. Most of these carvings were intended to be set into caskets (e.g., the Farnese casket in the Naples Gallery by Giovanni Bernardi, and a small coffer by Valerio Belli in the Pitti Palace in Florence), crosses, or candelabra (see the cross and candelabra by Antonio Gentili in the Treasury of St. Peter’s in Rome). Other crystal objects, such as paxes, crosses, or simple plaques, are found in all major collections. A fine portrait of Alessandro de’ Medici, carved by Domenico di Polo, is now in the Bibliothèque Nationale in Paris. In Germany, this art was imported from northern Italy. Artists such as the Miseroni family from Milan worked in Prague, while the Saracchi were active in Munich. Francesco Gundelach derived his art from their influence. A major production center for crystal developed in Bohemia from the 16th century onward. In the 17th century, glass, being less expensive, contributed to the decline of worked crystal. Only for the decoration of chandeliers (toward the end of the 18th century) and in the Neoclassical period, when exceptionally fine carvings were executed, was this noble material occasionally used again. — See pl. LVI.