Introduction dating methods
The heated enamel, after being thoroughly stirred, is usually poured out onto a slab and allowed to solidify into cakes of approximately four to five inches (10 to 13 centimetres) in diameter.
With the painted enamels of the Renaissance and the portrait miniatures of the 17th century, the technique reached its most ambitious and artistic form, in which the craftsman attempted to create a version of an oil painting, using a metal sheet instead of a canvas and enamels instead of oil paints.
This medium undoubtedly has its limitations—few painted-enamel plaques of the Renaissance, for example, are much more than one foot square—but while oil paints on canvas eventually fade and darken, the colours of enamels are permanent.
Throughout the Middle Ages, both secular and ecclesiastical objects, such as chalices, cups, reliquaries, caskets, crosiers (a staff carried by bishops and abbots as a symbol of office), and spoons, were elaborately enamelled.
With the advent of painted enamels in the Renaissance, tableware was completely covered with enamel, and painted-enamel panels were used to decorate the ceilings and walls of rooms in the châteaus of France.
The firing of enamel takes only a few minutes, and the object is then withdrawn and allowed to cool.
Throughout history, jewelry has been made more colourful by the application of enamels.
The cloisonné technique is particularly suited to objects made of gold, such as jewelry.Relatively few creative artists of distinction have chosen to work in this medium, however, and it has tended to be purely decorative.Few types of metal objects have not, at some period, been enriched with enamelled decoration.Enamels have long been used to decorate the surface of metal objects, perhaps originally as a substitute for the more costly process of inlaying with precious or semiprecious stones but later as a decorative medium in their own right.Whereas paint on metal has a short life and, even when new, is overshadowed by the brilliance of the polished metal, enamelling gives the surface of metal a durable, coloured, decorative finish.White enamel is produced by adding stannic and arsenious acids to the flux, the quantity of the acid affecting the density, or opacity, of the enamel.