Zellige (mosaic and decorative clay tiles) manufacturing

That is what the zellige?
The zellige is a Moroccan-Andalusian architecture who was able to perfectly adapt to the contemporary styles of decoration while preserving a handicraft manufacturing mode. The zellige is a technique for making mosaics with the Assembly of small pieces of ceramic related by cement. The main feature of the zellige is that drawings are performed backwards (see the realization of the mosaic). Thus made mosaics, are used as decoration for the mosques, fountains, houses and furniture.

History of the zellige
In the Morocco the zellige appeared in the 10th century in shades of white and Brown, the art of the zellige developed in the 14th century during the reign of the Merinids, with the use of the Green, and yellow. Red will be used only in the 17th century. The ancient decorations to the natural hues have been used until the end of the 20th century and the colors had probably not much changed since the period of the Merinids. Today, the colormap of the zellige was particularly enriched in bright colours.

Realization of the clay tiles
Matter first for ceramic tiles is the grey clay. It is mixed with water in basins for a week to get an overall homogeneous. This resulting dough is then cast in templates (mussels wood) for the clay tiles that go dry for several days in the Sun.

Realization of ceramics
One side of the clay tiles is soaked in colour and then dried face against face before moving on to cooking for a period of eight hours.
Ovens are composed of two parts: the home and the cooking Chamber. The walls of the furnace are made of clay and straw.
The fuel used is olive to start the oven and then the waste of the olives pressed from crush is a catalyst (is a substance which increases the speed of a chemical reaction). The temperature can rise up to 1200 ° C. Soil of the cooking Chamber is located above the fireplace and is pierced with several holes for the diffusion of heat. The clay tiles are arranged in several floors. At the level of the first floor are located the cold colours (white, blue, beige) and then halfway up the yellow, green, and Red at the top.  The cooking Chamber is then closed by a door sealed with clay soil. Once cooked the color of the tiles has become resplendent with silica and took his final hue.

Ceramic tiles are now ready to be used for the zellige.

Realization of mosaic
"Engineers" (masters) prepare the drawings to be used as models in the zelligeurs. These drawings also explain different forms to be cut in ceramics (square, Star, diamond, form rounded,...). The cutting of shapes is performed by three workers. The first trace the designs on the ceramic tile with a small brush. The second cut form a special hammer and finally the third provides the finishing in the Beveling. In General, the form of a piece of pottery is associated with a color for a model. This allows the zelligeurs to identify the color because they work upside down. For models where several colors can be associated with a form, they painted ceramic tip below to identify themselves.

First of all, the zelligeur must realize the framework or the mould of his model on the ground. This framework is generally produced in iron. Then the zelligeur poses forms depending on the model to achieve. The ends are maintained between them by a light layer of cement as a first step. Once the work completed, the cement is poured on the zellige where iron bars used to solidify the whole will be drowned.
Once dried, it remains only to return the whole! For large parts such as doors of mosques, cut into several pieces the mosaic that is numbers, and that it will bring together once as a puzzle.

Realization of the color of the tiles
The color is obtained by a mixture of metal ore and silica that will be cooked in an oven for several hours. According to the used ore the final color will be different. For example blue is obtained with cobalt. Once cooked, this mixture is associated to the water to obtain a well homogeneous paste.