METAL EMBELLISHMENTS -PAINTED ENAMELS

Post 501  by Gautam Shah

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Surface finishing or decorating with a foreign material is a very ancient technology. Metals have been embellished by several techniques. Metals have been coated by metal plating, surface alloying and deposition. Metals have been inlayed with metals, precious stones and objects.

Vairochana_Buddha,_China,_Qing_dynasty,_19th_century_AD,_jade,_gilt_bronze,_enamel,_pearls,_kingfisher_feathers_-_Royal_Ontario_Museum_-_DSC03754

These include:

Damascening a technique of encrusting gold, silver or copper wires in the finely chased surfaces of iron, steel, or bronze.

Niello is made from black metallic alloy of sulfur with silver, copper, or lead. It is filled in chased or engraved patterns over silver. The surface is heated for the niello to melt. On polishing the surface gets a dual metallic effect.

Granulation is made by soldering or fusing granulated beads of silver or gold to effect a bloom to the surface than of a beaded surface.

Filigree is made by forming a fine network of very thin wires fused selectively and than fixed on a metal surface of an object.

Ajouré is similar to filigree but the fine network is created by cutting or piercing the patterns in the metal. Raised patterns or cut out motifs are also fused onto the surface.

Embellishments with Other Materials were formed using precious stones, exotic substances such as rare woods, metals, ivory, horn, beads, sea shells, jade, and amber, and niello-work, fixed into chased or performed cavities or depressions. Fixing was by wire, metal forming, heat-fusing, thread knitting and knotting.

Inlay works are of many varieties. Pre-formed cavities or depressions are filled in by many different materials such as wood, stones and metals. The fixing is with tight fitting, adhesives, or by hammering a ductile metal.

Gilding is application of metal like silver, gold, silver, palladium, aluminum, and copper alloys, in the form of very thin foils. Gilding by gold or silver foils requires as no adhesives as sufficient electrical charges attract the foil to the base, however for permanent fixing (on exterior use) some form of adhesives are used.

Overlays can be defined as metal sheathing or cladding by metal sheets that are slightly heavier than used for gilding. Overlaying is also done by applying a gold amalgam (gold+mercury) and than removing the mercury with heat.

painted enamel on copper 290x 240mm

Enamelling is a metal embellishment technique wherein a vitreous glaze is heat-fused to create a very long lasting decorative effect of brilliant colours. (Read on > Enamels).

Snuff bottle, northern India, 18th century, gold, gemstones and enamel

An Enamel is a compound of flint or sand, red lead, and soda or potash which forms a glass like material on being melted. Low temperature fusing is easier to manage, but creates a soft glass surface that is prone to cracking. Hard enamels are formed at higher temperature are better lasting, but it is a slightly difficult process.

Miniature of Marie Louise d’Orléans, future Queen of Spain by Jean Petitot le vieux (1607-1691)

Painted Enamels are like miniature oil paintings. These are made on a metal base or plate covered with a layer of an opaque enamel. The opaque or white enamel base is further embellished with ‘glass forming but with colouring materials’, rendered by fine needle painting, spraying, screen printing, spattering, scratching or block printing. Separate firing is required for each of the colours. Artists created portraits and other art subjects on very small metal plates, surpassing richness of larger canvass-based oil paintings. Painted Enamels being very small could be carried anywhere as a personal item of collection or treasure. The colours are permanent and non-yellowing or fading. The painted enamel has remained a craft and is not accepted as medium of art. The painted enamels of China are known as Canton (Guangzhou) enamels. Painted enamels are termed by the Chinese yangci (foreign porcelain).

Coloured enamel embellishments were created over arms, armour, mirrors, bowls, cups, chalices, spoons, and miniature pendants, tableware, wall and ceiling panels, signages, table clocks, and snuffboxes.

‘Mercury’, painted enamel and gilt on copper mirror back

Five main types of enamelling processes are used:

Champlevé (French= raised field) enamels are created by scratching or etching a copper surface, which are than filled-in with pulverized enamel material, fired and polished.

Cloisonné (French= partitioned) has very small partitions or cloisons formed with thin metal strips. The partitions are filled with pulverized enamel and fired.

Basse-Taille (French= low cutting) process is a kind of champlevé, but is applied to silver or gold. Here the depressions are filled with translucent enamel, which allows the substrate or patterns on it to be seen.

Plique-à-jour (French=open braids) enamelling resembles cloisonne, but here the partitions form a separable lattice. The lattice is removed after firing, giving an effect of stained glass. It is exceptionally fragile work.

Encrusted Enamel: Encrusted enamel or enamel en ronde bosse is prepared by spreading of an opaque enamel paste over slightly roughened surfaces of objects such as small figures.

Binding representing the Crucifixion of Christ, Limoges (Limosin, France) champlevé enamel on gilded copper

 

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ENAMELS

Post 340 ⇒   by Gautam Shah 

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An enamel is the hardest substance in the human body, in the form a cover on the teeth, consisting chiefly of calcium salts. Substances similar in hardness were produced through a glass-ceramic route. The word enamel derives from smelting or smelzan (German) or smalto (Italian), email (French and German), and enamel (English). Smelting as a process is very old, used for extracting metal by heat processing the mineral ore. Enamelling uses similar processes of material conversion.

10th C gold and enamel Byzantine icon of St Michael, St Mark Basilica

Enamel, is defined as a vitreous, glass like coating fused on to a metallic base. Through the history, enamels have been applied on gold, silver, copper, bronze and iron surfaces. The term is also used for many other applications that provide tough and a glossy surface such as the fusing of glass over glass, fired ceramics, and paints.

Enamel is formed from substance known as flux, frit or fondant. For enamelling the paste consisting of mixture of silica (from quartz or sand), soda or potash, and lead are deposited on to metal objects such as jewellery, small metal boxes, utensils, ceramics or glass, and fused by heat. The resultant surface is chemically identical to glass or highly vitrified ceramic, almost clear, with a slightly bluish or greenish tinge. The surface can be made opaque and coloured by the addition of other metallic oxides. When the temperature to fuse the materials is very high, the enamel formed is hard. Soft enamels are easy to produce and are more conventional.

Enamelled Signage

The brilliance of an enamel depends on the perfect combination of its ingredients and temperature. The colour is achieved by a change in the proportion of the ingredients of the flux than by an increase in quantity of the oxide.

Enamel Watch dial

The earliest known enamelled objects were made during the Mycenaean period during 13th C BC. Since then through history jewellery had applique colours of enamels. Arms’ handles and armour cases, mirrors, furniture handles, decorative dishes and bowls were embellished with enamel. Ceilings’ and doors’ metal panels were enamelled. Religious ceremony items such as cups, bowls, caskets, crosiers, were enamelled. Dials of table, pocket and wall clocks were adorned with enamelled numbers. In India jewellery and small boxes were enamelled, known as Minakari work.

enamel-ware-on-shelf

White Enamel ware Image from PublicPicturesDomains.net

With the onset of 18th C., Cast iron vessels for home and other uses began to be used. These enamelware were with little colour or patterns. The vessels with white enamel coating were known as white-ware. Hospital-ware such as gandy, urine pot, kidney tray, instruments’ tray, camping-ware and army-ware like tumbler, bowls, dishes, and public signages were made with enamelling. The white vitreous enamel linings, was also called porcelain. It was used for lining cooking stoves tops, oven doors, sinks and washbasin.

Stove -White Enamel goods

There are two main methods of applying enamel to metal. Champlevé, in which hollows made in the metal surface are filled with enamel, and Cloisonné, in which strips of metal are applied to the metal surface, forming cells, which are then filled with enamel. With these two basic methods Six types of enamelling techniques have developed: These are Champlevé, Cloisonné, Basse-taille, Plique-à-jour, Encrusted, and Painted enamel.

Champlevé type 12th C armlet, so showing chased recesses for the enamel

1 Champlevé (French= raised field) enamels are done by scratching or etching a metal surface, usually copper, leaving hollows or troughs with raised lines between them. The hollows are filled with pulverized enamel and then fired. The hard-finished enamel is subsequently filed down until the glossy surface and the metal surface can be polished simultaneously, with crocus powder and jeweller’s rouge.

Cloisonné enamel plaque, Byzantine Empire, ca. 1100

2 Cloisonné (French= partitioned) processes, uses very small partitions, or cloisons, consisting of thin metal strips, built up on the surface of the metal. They may present a pattern and are fixed to the surface by the enamel. The Cloisonné technique is usually applied to silver, although gold or copper may also be used as bases. Cloisonné techniques originated in 4000 BC.

Basse-Taille type enamel Royal Gold Cup, 236 high x 178 across 14 C

3 Basse-Taille (French= low cutting) process is a kind of champlevé but is applied to silver or gold. The metal is engraved or hammered to various depths according to the design. The depressions are then filled with translucent enamel, through which the design beneath it can be seen.

Silver-gilt set with plique á jour enamel plaques, and gold cell-work

4 Plique-à-jour (French=open braids) enamelling resembles cloisonne, but differs from it in that the partitions are soldered to each other rather than to the metal base, which is removed after firing. The remaining shell of translucent enamel gives the effect of stained glass. Plique-à-jour enamel is exceptionally fragile because it has no metal base.

Gold, encrusted (en ronde bosse) enamelling 1517

5 Encrusted Enamel or enamel en ronde bosse, involves the spreading of an opaque enamel paste over the slightly roughened surfaces of objects such as small figures.

Pocket Watch, 1750-1800, painted enamel portrait

6 Painted Enamels resemble small oil paintings. A metal plaque is covered with a layer of white enamel and fired. The design in coloured enamels, is then applied to the white ground, by painting, spraying, screen printing, or block printing, separate firing may be required for each colour because each may fuse at a different temperature. Painted enamelled miniature portraits were popular in Renaissance period.

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