Ancient
The earliest enamel all used the cloisonné technique, placing the enamel within small cells with gold walls. This had been used as a technique to hold pieces of stone and gems tightly in place since

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Vitreous enamel can be applied to most metals. Most modern industrial enamel is applied to steel in which the carbon content is controlled to prevent unwanted reactions at the firing

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• The three main historical techniques for enamelling metal are:
Variants, and less common techniques are:
• Ronde bosse

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Enamel coatings applied to steel panels offer protection to the core material whether cladding road tunnels, underground stations,

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• Franz Ullrich – founder of a German enamelware factory
• Fred Uhl Ball – American enamellist who created the largest known enamel mural
• Oskar Schindler

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1. ^ Campbell, 6
2. ^ Chisholm, Hugh, ed. (1911). "Enamel" . Encyclopædia Britannica (11th ed.). Cambridge University Press.

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On sheet steel, a ground coat layer is applied to create adhesion. The only surface preparation required for modern ground coats is degreasing of the steel with a mildly alkaline

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