''Plique-à-jour'' (French for "letting in daylight") is a

vitreous enamel Vitreous enamel, also called porcelain enamel, is a material made by melting, fusing powdered glass to a substrate by firing, usually between . The powder melts, flows, and then hardens to a smooth, durable vitrification, vitreous coating. The wo ...

ling technique where the enamel is applied in cells, similar to

cloisonné Cloisonné () is an ancient technology, ancient technique for decorating metalwork objects with colored material held in place or separated by metal strips or wire, normally of gold. In recent centuries, vitreous enamel has been used, but inla ...

, but with no backing in the final product, so light can shine through the transparent or translucent enamel. It is in effect a miniature version of

stained-glass Stained glass refers to coloured glass as a material or art and architectural works created from it. Although it is traditionally made in flat panels and used as windows, the creations of modern stained glass artists also include three-dimensio ...

and is considered very challenging technically: high time consumption (up to 4 months per item), with a high failure rate. The technique is similar to that of

, but using a temporary backing that after firing is dissolved by acid or rubbed away. A different technique relies solely on

surface tension Surface tension is the tendency of liquid surfaces at rest to shrink into the minimum surface area possible. Surface tension (physics), tension is what allows objects with a higher density than water such as razor blades and insects (e.g. Ge ...

, for smaller areas. In Japan the technique is known as shotai-jippo (shotai shippo), and is found from the 19th century on.

History

The technique was developed in the

Byzantine Empire The Byzantine Empire, also known as the Eastern Roman Empire, was the continuation of the Roman Empire centred on Constantinople during late antiquity and the Middle Ages. Having survived History of the Roman Empire, the events that caused the ...

in 6th century AD. Some examples of Byzantine plique-à-jour survived in

Georgia Georgia most commonly refers to: * Georgia (country), a country in the South Caucasus * Georgia (U.S. state), a state in the southeastern United States Georgia may also refer to: People and fictional characters * Georgia (name), a list of pe ...

icon An icon () is a religious work of art, most commonly a painting, in the cultures of the Eastern Orthodox, Oriental Orthodox, Catholic Church, Catholic, and Lutheranism, Lutheran churches. The most common subjects include Jesus, Mary, mother of ...

s. The technique of plique-à-jour was adopted by

Kievan Rus' Kievan Rus', also known as Kyivan Rus,. * was the first East Slavs, East Slavic state and later an amalgam of principalities in Eastern Europe from the late 9th to the mid-13th century.John Channon & Robert Hudson, ''Penguin Historical At ...

(a strong trading partner of

Constantinople Constantinople (#Names of Constantinople, see other names) was a historical city located on the Bosporus that served as the capital of the Roman Empire, Roman, Byzantine Empire, Byzantine, Latin Empire, Latin, and Ottoman Empire, Ottoman empire ...

) with other enamel techniques. Despite its complexity plique-à-jour tableware (especially " kovsh" bowls) was used by its aristocracy. Russian masters significantly developed plique-à-jour technique: in addition to cells cut in precious metal they worked with cells made of silver wire. Unfortunately the plique-à-jour technique of Kievan Rus' was lost after the crushing

Mongol invasion The Mongol invasions and conquests took place during the 13th and 14th centuries, creating history's largest contiguous empire, the Mongol Empire (1206–1368), which by 1260 covered large parts of Eurasia. Historians regard the Mongol devastati ...

in the 13th century. Some surviving examples are exhibited in the Historical Museum in Moscow. Western Europe adopted the plique-à-jour technique (cells cut in metal) of Byzantium. The term ''smalta clara'' ("clear enamel"), probably meaning ''plique-à-jour'' appears in 1295 in the inventory of

Pope Boniface VIII Pope Boniface VIII (; born Benedetto Caetani; – 11 October 1303) was head of the Catholic Church and ruler of the Papal States from 24 December 1294 until his death in 1303. The Caetani, Caetani family was of baronial origin with connections t ...

and the French term itself appears in inventories from the 14th century onwards.

Benvenuto Cellini Benvenuto Cellini (, ; 3 November 150013 February 1571) was an Italian goldsmith, sculptor, and author. His best-known extant works include the ''Cellini Salt Cellar'', the sculpture of ''Perseus with the Head of Medusa'', and his autobiography ...

(1500–1571) gives a full description of the process in his Treatises of Benvenuto Cellini on Gold-smithing and Sculpture of 1568. Pre-19th century pieces are extremely rare because of their "extreme fragility ... which increases greatly with their size", and the difficulty of the technique. Survivals "are almost exclusively small ornamental pieces". The outstanding early examples that survive are "the decorative insets in the early fifteenth-century

Mérode Cup The Mérode Cup is a medieval silver-gilt cup decorated with finely engraved birds, fruit and vine leaves. It was made in France in Burgundy in about 1400, and was named after the ancient Belgian family of Mérode, to whom it once belonged. It is ...

(Burgundian cup) at the

Victoria and Albert Museum The Victoria and Albert Museum (abbreviated V&A) in London is the world's largest museum of applied arts, decorative arts and design, housing a permanent collection of over 2.8 million objects. It was founded in 1852 and named after Queen ...

in London, a Swiss early sixteenth-century plique-à-jour enamel plaque representing the family of the Virgin Mary in the

Metropolitan Museum of Art The Metropolitan Museum of Art, colloquially referred to as the Met, is an Encyclopedic museum, encyclopedic art museum in New York City. By floor area, it is the List of largest museums, third-largest museum in the world and the List of larg ...

in New York, and the eight pinnacle points over the front of the eleventh-century Saint Stephen's Crown in Hungary". The technique was lost in both Western and Eastern Europe. The technique was revived in the late 19th century movement of revivalist jewellery, and became especially popular in Russia and Scandinavia. Works by Pavel Ovchinikov, Ivan Khlebnikov, and some masters working for Faberge are real masterpieces of plique-à-jour. Russian masters predominately worked with tableware. Norwegian jewellers included David Andersen and J. Tostrup in Oslo, and Martin Hummer in Bergen.

Art Nouveau Art Nouveau ( ; ; ), Jugendstil and Sezessionstil in German, is an international style of art, architecture, and applied art, especially the decorative arts. It was often inspired by natural forms such as the sinuous curves of plants and ...

artists such as

René Lalique René Jules Lalique (; 6 April 1860 – 1 May 1945) was a French jeweller, medallist, and glass designer known for his creations of glass art, perfume bottles, vases, jewellery, chandeliers, clocks, and automobile hood ornaments. Life Lalique ...

Lucien Gaillard Lucien Gaillard (1861 – 1942, both in Paris, France) was a French goldsmith and jeweller, who worked in the art nouveau style. Lucien Gaillard was born into a family of jewellers. His grandfather Amédée Alexandre Gaillard (1811-1882) founded ...

and other French and German artists predominantly used plique-à-jour in small jewellery, though the Victoria & Albert Museum has a tray of 1901 by

Eugène Feuillâtre Eugene is a common male given name that comes from the Greek εὐγενής (''eugenēs''), "noble", literally "well-born", from εὖ (''eu''), "well" and γένος (''genos''), "race, stock, kin".Ring-tray by Eugene Feuillâtre
V&A. Currently plique-à-jour is not often used, because it is challenging technically and mainly because of breaks in transferring skills from one generation of jewellers to the next. However, some luxury houses do produce limited numbers of products in the plique-à-jour technique, for example Tiffany in jewellery, and Bulushoff in jewellery and tableware. Works in the ''shotai shippo'' technique are also known from China and Iran.

Techniques

There are four basic ways of creating plique-à-jour: 1. Filigree plique-à-jour ("Russian plique-à-jour"): This is a building up process whereby a planned design is interpreted using gold or silver wires which are worked over a metal form (e.g. a bowl). Wires are twisted or engraved, i.e. have additional micro patterns. The wires are soldered together. Enamels are ground and applied to each "cell" created by the metal wirework. The piece is fired in a kiln. This process of placing and firing the enamels is repeated until all cells are completely filled. Usually it takes up to 15–20 repeats. 2. Pierced plique-à-jour ("Western plique-à-jour"): A sheet of gold or silver is pierced and sawed, cutting out a desired design. This leaves empty spaces or "cells" to fill with enamel powders (ground glass). 3. ''Shotai shippo'' ("Japanese plique-à-jour"): A layer of flux (clear enamel) is fired over a copper form. Wires are fired onto the flux (similar to

) and the resulting areas are enameled in the colors of choice. When all the enameling is finished, the copper base is etched away leaving a translucent shell of plique-à-jour. 4. Cloisonné on mica: Cells in precious metal are covered with fixed mica, which is removed by abrasives after enameling.

Process for cloisonné plique-à-jour on mica

Sample process

File:Plique-à-jour enamel technique 1.jpg, 1.

Mica Micas ( ) are a group of silicate minerals whose outstanding physical characteristic is that individual mica crystals can easily be split into fragile elastic plates. This characteristic is described as ''perfect basal cleavage''. Mica is co ...

is used to stop the enamel powder from flowing out when it is heated up. It can resist high temperature and enamel won't stick to it. File:Plique-à-jour enamel technique 2.jpg, 2. Blocks of mica are made of thin sheets. Select one larger than the piece that will receive the enamel. File:Plique-à-jour enamel technique 3.jpg, 3. The shape of the object to receive the cloisonné enamel is cut out from the mica sheet. File:Plique-à-jour enamel technique 4.jpg, 4. A sheet of copper is also cut out. It needs to be large enough to be folded on the sides of the piece. File:Plique-à-jour enamel technique 5.jpg, 5. The piece and the mica sheet are carefully wrapped in the copper foil. It is important that the copper folds do not touch the parts that will be enamelled File:Plique-à-jour enamel technique 6.jpg, 6. Enamel powder comes in different colors. File:Plique-à-jour enamel technique 7.jpg, 7. The enamel powder first needs to be washed. File:Plique-à-jour enamel technique 8.jpg, 8. The cleaner the color, the clearer the enamel. File:Plique-à-jour enamel technique 9.jpg, 9. The enamel powder is applied wet. Capillary action helps filling the shapes and reduces the space between the grains of color. This prevents bubbles from forming as the piece is fired. File:Plique-à-jour enamel technique 10.jpg, 10. The enamel must be applied layer by layer since it collapses during firing. At the same time, care should be taken that the grains do not spread over the edge. File:Plique-à-jour enamel technique 11.jpg, 11. The enamel powder is left to dry completely. If the powder is still humid, the enamel will form bubbles. These will burst and spread liquid enamel on the piece and inside the oven. File:Plique-à-jour enamel technique 13.jpg, 12. Meanwhile, the oven is preheated (in this case to 825 °C). Plique-à-jour enamel technique 12.jpg, 13. After the oven has been preheated at the desired temperature and the enamel powder has completely dried, the pieces can be placed inside. File:Plique-à-jour enamel technique 14.jpg, 14. As soon as the enamel is melted, the firing is done. Since this is a fairly quick process (around a minute or less at this temperature), the firing is monitored through a peephole to make sure the enamel is not overheated. File:Plique-à-jour enamel technique 15.jpg, 15. The pieces need to cool down slowly. File:Plique-à-jour enamel technique 16.jpg, 16. Once the piece has cooled down, new enamel powder can be applied a second time if necessary. File:Plique-à-jour enamel technique 17.jpg, 17. The copper foil and the mica are then removed. File:Plique-à-jour enamel technique 18.jpg, 18. Excess enamel is removed with an aluminum-oxide-abrasive mounted wheel. File:Plique-à-jour enamel technique 19.jpg, 19. It is dangerous to breathe the dust produced by the use of the drill. The pieces are kept wet to prevent dust from flying into the air. File:Plique-à-jour enamel technique 20.jpg, 20. The surface of the piece is then levelled and smoothed out with sanding paper. File:Plique-à-jour enamel technique 21.jpg, 21. The pieces are then cleaned from the sanding dust. File:Plique-à-jour enamel technique 22.jpg, 22. Minor flaws can now be fixed. Gum tragacanth is added to the wet powder to keep it in place for the last firing. File:Plique-à-jour enamel technique 23.jpg, 23. The last firing gives shine to the enamel. It is important here that the enamel has no contact with the support. File:Plique-à-jour enamel technique 24.jpg, 24. The last firing also makes the enamel more translucent. It is the trickiest step since the enamel will fall out if it liquefies. File:Plique-à-jour enamel technique final.png, 25. The creatures are ready for their first flight!

Notes

References

*Campbell, Marian. ''An Introduction to Medieval Enamels'', 1983, HMSO for V&A Museum, *Ostoia, Vera K., "A Late Mediaeval Plique-à-Jour Enamel", ''The Metropolitan Museum of Art Bulletin'', New Series, Vol. 4, No. 3 (Nov. 1945), pp. 78–80
JSTOR

External links

* {{DEFAULTSORT:Plique-A-Jour Artistic techniques Vitreous enamel