What is 'Email brun'?

Although Email Brun resembles dark brown enamel, it is really something quite different. It is linseed oil which is painted on a clean, annealed piece of copper.

After drying, the layer is fired at a low temperature. After the first firing, the surface is a darkish brown. If you are looking for a darker shade, just paint on a second layer (or more layers until you are satisfied).

If you like etching, you may use your etching utensils and work in the layer of dried linseed oil as if it were a regular etching ground.

Engraved lines and surfaces, not covered with linseed oil, were often gilded, thus contrasting beautifully with the chestnut brown surface.