Maiolica is a type of ceramic where decoration is applied to an unfired white glaze. This is a overview of the steps used to decorate an unglazed commercial clay tile using the maiolica technique.
A ceramic vessel is formed with clay, dried and fired in a kiln to bisque. White glaze is applied to the bisque by either dipping, pouring, or brushing onto the surface. The unfired glaze is applied so it is about 1 millimeter thick.
The pattern is transferred using the traditional technique known as pouncing. Loose graphite is rubbed through a series of holes poked in the lines of a pattern to transfer the design.
Here is a tile once the design has been transferred onto the white glaze by the pouncing technique. The loose graphite has been pushed through the holes and leaves the pattern on top of the white glaze.
Next the design is outlined following the dots left by the pouncing technique. The graphite can be easily smudged so it is touching is kept to a minimum. Once the outline has been done, the loose graphite can be brushed away using a large soft brush. The graphite will fire away in the kiln but brushing away the graphite makes it easier to paint shading.
After the outline is painted, the underglaze color is diluted with water to create a wash of color. Shading is done by adding washes of colors in layers. Layering helps minimize the shifting of the white glaze if it re-hydrates.
Here is the painted tile ready to be fired in the kiln. Before firing, a thin coat of clear is applied on top of the painted design. This is an optional step that gives a nice glossy finish to the piece. The pigment colors will sink into the white during firing, but some of the colors have a rough texture if a clear top coat is not applied. Some of the pigments may run if a fan shaped brush is used to apply the clear glaze. An air brush can be used to apply the clear top glaze to prevent smearing.
Here is the fired after it has been set into a box.