La Rochelle: Perched flat bird notice the red iron

Earthenware big fire

Earthenware is said to be "tin-bearing" when the ocher paste of the terracotta is covered with a white tin-based enamel called engobe. A distinction is made between high-fire and low-fire tin-bearing earthenware.
“great fire” when the decoration is placed, after “knowledgeable” pre-firing, directly on the tin enamel (opaque white) powder or engobe, which absorbs it without hope of repentance.
The colors capable of withstanding the great fire are produced by metallic oxides and limited to five (cobalt blue (the most used), brown-violet based on manganese, red and green from copper, yellow coming from antimony ), to which should be added the iron oxide giving the black.
The pieces undergo, after the decoration, their final firing. However, the mastery of these colors will be progressive, in particular for yellow and red, which support different temperature levels. For a long time, we will use an orange as a red and a yellow ocher for the yellow, which will make the decorations relatively unrealistic.

© Docteur francis Morin