enamel (fused coating)

A semi-transparent or opaque vitreous, porcelain-like coating applied by fusion to metal, glass, or ceramic, having a glossy appearance after hardening. Enamel is typically made from powdered fusible glasses and opaque colourants mixed with oil or water, then applied to the object and fired at a high temperature.

AAT

The Arts and Architecture Thesaurus Online, The Getty Research Institute.

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