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Vitreous Enamel: A Summary

• Vitreous enamel is a material made by fusing powdered glass to a substrate by firing, which creates a smooth, durable coating.

• Enamel can be used on metal, glass, ceramics, stone, or any material that can withstand the fusing temperature.

• Enamelling is an old and widely adopted technology, mainly used in jewellery and decorative art, but since the 18th century, enamels have been applied to many metal consumer objects, such as cooking vessels, sinks, bathtubs, appliances, marker boards, and signage.

• The term "enamel" has sometimes been applied to industrial materials other than vitreous enamel, such as enamel paint and the polymers coating enameled wire.

• The earliest undisputed objects known to use enamel are a group of Mycenaean rings from Cyprus, dated to the 13th century BC.

• In European art history, enamel was at its most important in the Middle Ages, beginning with the Late Romans, and then the Byzantine, who began to use cloisonné enamel in imitation of cloisonné inlays of precious stones.

• Limoges enamel was made in Limoges, France, the most famous centre of vitreous enamel production in Western Europe, though Spain also made a good deal.

• Cloisonné remained very popular in China until the 19th century and is still produced today. The most elaborate and most highly valued Chinese pieces are from the early Ming dynasty.

• Japanese artists did not make three-dimensional enamelled objects until the 1830s, but once the technique took hold, it developed very rapidly, reaching a peak in the Meiji and Taishō eras.

• Enamel was established in the Mughal Empire by around 1600 for decorating gold and silver objects, and became a distinctive feature of Mughal jewellery.

• More recently, enamel is a favoured choice for jewellery designers, including the Art Nouveau jewellers, for designers of bibelots, and for artists such as George Stubbs and other painters of portrait miniatures.

• Vitreous enamel has many useful properties: it is smooth, hard, chemically resistant, durable, scratch-resistant, has long-lasting colour fastness, is easy to clean, and cannot burn.The Art and Science of Enameling

• Buick automobile company was founded by David Dunbar Buick with wealth earned by his development of improved enamelling processes for sheet steel and cast iron.

• Enamelled ferrous material had many applications such as advertising signs, interior oven walls, cooking pots, and housing and drums of clothes washers and dryers, among others.

• Enamel is widely used in the production of quality chalk-boards and marker-boards where the resistance of enamel to wear and chemicals ensures that 'ghosting' or unerasable marks do not occur.

• The key ingredient of vitreous enamel is finely ground glass called frit.

• Frit for enamelling steel is typically an alkali borosilicate glass with a thermal expansion and glass temperature suitable for coating steel.

• Colour in enamel is obtained by the addition of various minerals, often metal oxides cobalt, praseodymium, iron, or neodymium.

• There are various types of frit which may be applied in sequence. A ground coat is applied first, followed by clear and semi-opaque frits that contain material for producing colours.

• There are three main historical techniques for enamelling metal: cloisonné, champlevé, and plique-à-jour.

• Industrial enamel application on sheet steel requires a ground coat layer to create adhesion. White and coloured second "cover" coats of enamel are applied over the fired ground coat.

• Enamel coatings applied to steel panels offer protection to the core material whether cladding road tunnels, underground stations, building superstructures or other applications.

• The qualities of enamel as a structural material include durability, corrosion resistance, and resistance to UV radiation.

• Enamel can be used to create beautiful and intricate designs on metal surfaces, and can be found in many art objects, jewelry, and decorative items.