How is black enamel applied?

The gold or silver piece is first cut out, then furnished with recessed fields (champlevé) or engraved. The finely ground glass frit is laid into the recesses and fired at about 800 °C - usually in several layers. After firing, the surface is ground flat and polished. A well-executed black enamel surface is deep black, glassily smooth and stable over decades.

Why was black enamel more expensive than jet?

The carrier metal - usually 18 or 22 carat gold - is the largest cost item. Added to this are the high demands on craftsmanship: the champlevé recesses must be exact, the firing is risky (cracks, bubbles, discolouration), and the inscription is usually engraved only after firing. A Victorian mourning ring in black enamel cost roughly ten times as much as a comparable jet piece.

What is the difference between enamel and niello?

Both fill recessed fields in metal with a black mass. Enamel is fired glass, niello a fusible alloy of silver, copper, lead and sulphur. Enamel is visually glassy and smooth, niello matt and metallic. Niello is more robust against knocks, enamel more delicate but deeper in colour. Both techniques are documented in mourning rings; in the High Victorian period enamel dominated (see Niello (Black Inlay Technique)).

Black Enamel (Schwarzemail)

Black enamel is a glass frit coloured with manganese oxide and fused in thin layers onto gold or silver - the most expensive variant of Victorian mourning jewellery and the preferred carrier ground for inscriptions.

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