Coloured enamel can be produced either by grinding highly friable coloured glass, or by adding specific minerals – usually oxides – to clear glass.

The most often used minerals are metal oxides such as cobalt (blue), praseodymium (yellow), iron (green), tin (bright white), gold (red) or neodymium (which can give differing hues from violet, to wine red, to warm grey).

Coloured enamel can be opaque, transparent or translucent, the latter getting more and more “milky” the longer it is fired.

Unlike paint, different colours of opaque enamel do not mix, so you can’t, say, use blue and yellow to make green.

Instead, mixing enamel colours results in that beautiful “flecked” look – blue with yellow flecks or yellow with blue flecks, depending on the amounts of colour used. Although, a clever artisan can grind the two colours so finely that the eye is tricked.

Also mixing opaque and transparent enamels in combinations of two or more can produce some amazing effects.

For example, an opaque yellow, overfired with transparent blue would produce a green affect – but a close look would uncover that the eyes are, once again, being deceived.

Designers often mix and match various techniques and bring out lovely colours in their enamel artworks.

Getting the best colours from enamel requires specific skills that are, unfortunately, being lost in these modern times.