inJanuary 14, 2008 - 11:29am
Enamel is the hard vitreous substance (composed of glass and inorganic pigments used to produce color) fused to a metal jewelry object through the use of heat, and enameling is the technique by which the substance is applied. The object is heated until the glass begins to soften and flow. Enamels come in a variety of forms including: powdered enamels (most commonly used), painting enamels, watercolor and acrylic enamels, and other interesting forms. Enamel for metal is made by combining raw minerals according to a specific formula to produce a particular type and color of enamel. The mixture may contain silica, soda ash and potassium nitrate. It may also be made of feldspar, quartz, borax, calcium phosphates and kaolin. Ceramic pigments are added to the glass to control color; and in some formulas, oxides are combined with glass to create color.
Early artisans were fascinated by glass, and it was this fascination that fueled the development of enamels and enameling techniques shortly after the discovery and use of glass. The history of enamels and enameling techniques covers several millennia, dating back to early dynastic times in Egypt, Samaria, and Mesopotamia. Ancient craftspeople used enamels as a replacement for gemstones in the making of jewelry and ceremonial objects. Specific colors of glass were substituted for specific gemstones; for example, cobalt blue was used as a replacement for rare lapis lazuli, and opaque blue-green was used as a substitute for turquoise.
One of the earliest techniques used was Cloisonné (cloy-zoh-nay) enameling, where very thin metal wires are attached to a metal surface to create small cells (cloisons). The wires serve to keep the colors separated, and to add decorative elements to the design. The cells are inlayed with enamel and fired in layers until the glass is level with the top of the wires. This technique was developed in Egypt before 1800 BC, although the name cloisonné was not applied until the eighteenth century. Cloisonné enamel is the easiest of all the techniques to identify, as the metal wires are very recognizable.
Champlevé (shomp-luh-vay) enameling is similar to cloisonné in that the enamel is inlayed into recessed compartments separated by metal. However, in Champlevé enameling, cells are created by engraving, chiseling, fabrication, etching, stamping or carving the metal base, leaving a raised metal line between the cells, which form the outline of a design. The cells are then inlayed with enamel. The name Champlevé comes from the French words “champ,” a field, and “levé,” raised. The Celts of the British Isles are believed to have been the first craftsmen to start working in Champlevé enameling during the 3rd century.
Basse-Taille (bahs-tah-ee) enameling (French for “low cut”) was first introduced in 14th century Italy. The term is used to describe enamel pieces that are made using a sheet of etched, engraved, or impressed metal topped with a thin layer of transparent enamel, which allows the pattern of the metal surface to show through. Because the design has high and low points, the enamel will be thicker in some areas than others, which with glass translates to a dark color value in the low (recessed) areas, and a light color value in the high (raised) areas of the design.
It was in the city of Limoge, Paris, in the 15th and 16th century, that painting with enamels first became popular and flourished. One painting technique is called Grisaille enameling which comes from the French word “gris,” meaning gray. The Grisaille enameling technique uses primarily gray tones. It is a wet technique, and is applied in much the same way as an artist would apply oil paint to canvas. A base coat is applied over metal, and successive thin layers of colored enamels are blended and shaded in a painterly fashion to build up values and create dimension. Painting with enamels requires great skill and control, and is considered to be the most difficult enameling technique to master.
The Guilloché style of basse taille enameling is perhaps the most commonly referenced type of enameling in vintage and antique jewelry today. The Guilloché style was developed in the late 1800’s, during a time of great industrial growth in the U.S. and throughout Europe, and after engraving lathes were developed. This technique refers to a type of abstract geometric pattern cut into the surface of metal with a layer of transparent enamel applied over the top allowing the design to show through. The introduction of metal lathes allowed a variety of machine turned surfaces to be made with continuous patterns and designs, from moiré patterns to wave designs. Guilloché enameling was very popular in Victorian and Edwardian jewelry, and is easy to recognize because the transparent glass allows you to see the machine lathed, engine turned designs clearly.
Plique-à-Jour (pleek-a-jour) enameling looks like a miniature stained glass window. The colors and metalwork in properly executed Plique-à-Jour enameling are beautiful. The term is a derivative of partly Italian and partly French origins, meaning: “similar to a membrane (plique) stretched in a way that the light of day (à jour) may pass through.” Plique-à-Jour is filigree metalwork surrounding glass. The open filigree or wire framework is inlayed with wet enamels and held in place by surface tension. This type of enamel work was very popular during the Art Nouveau period.
Color is also added to jewelry and decorative objects using “cold enamels” – made from resin, plastic or paint. These substances, when applied correctly, give the appearance of enamel, and are generally used in the production of costume jewelry and some sterling silver items. Cold enameling is an inexpensive way to add color to a piece, but the results are not nearly as beautiful as true enamel, or as durable.