Who has not marvelled at the beautiful borders that run around the walls of the Alhambra? Yard upon yard of panel work incrusted with a symphony of exquisitely intermingled "aliceres" (tiny pieces of tile cut with a pick) and friezes.

This is perhaps the most outstanding example of Spain's great tradition of using decorative complementary pieces, yet it was the Modernist movement that brought them into the limelight.

As their name implies, complementary pieces are designed to enhance aesthetically. Pointless on their own, they become meaningful as part of a whole.

On the other hand, there are so-called "special pieces" which, in contrast to the purely decorative nature of complementary pieces, perform some sort of "special" function (to create skirting boards, beading, handrails, steps and so on).

What is available?
A plethora of different formats of decorative pieces abounds today for both floor and wall tiles.

For flooring: borders, tacos, dots (these differ from tacos by being smaller and being laid in a special way; also they are usually made of white stoneware, decorated with heraldic motifs in blue and tend to be combined with Catalan tiles), lozenges and many more.

Systems are also part of the range of complementary pieces. These are sets of pieces of different sizes, shapes and colours that together fulfil a common function or purpose - for instance creating floor decoration designs such as rosettes and repeat modular pieces.

Complementary pieces for walls include friezes, listellos, centre decorations, coving and edging, angles, dados and scotias, moulded edgings and many more.

Decor and third firings
For the most part, the decor is applied to complementary pieces by a process known as "third firing". The term refers to the way tiles are made, which includes two firings, the first to produce the base or biscuit, the second to vitrify the glaze and set the decor that is applied to the crude glaze. The glazed pieces are then decorated and this decoration has to be fixed by being fired for a third time - hence the term "third firing".

Formerly, third firing decoration was carried out in small, independent workshops, and was generally painted freehand or with the help of a stencil or transfers.

Applying décor by using stencils reached its zenith in Spain during the Modernist movement with traditional designs and designs inspired by "art nouveau" and "art déco". There was, however, no way of automating the use of stencils, so the practise was for the most part abandoned or, where it was retained, became impoverished.

The market was increasingly calling for product diversification and serial production, which was already a pre-requisite for containing costs, was not appropriate for producing small runs of a long list of complementary pieces such as listellos and dots that were increasingly in demand.

Production plants began to appear that were comparable with those of the tile industry in terms of size, equipment, systems and mechanisation. Varied and sophisticated decorative and production techniques were adopted and making complementary pieces ceased to be a marginal activity, becoming instead an ancillary, or should we say complementary, industry in its own right within the greater ceramic tile industry.

The main feature of recent years has been heavy investment in machinery and new processes. The most recent trends in third firing decorated pieces are lustre and metallic finishes, under-glaze screen printing, hand painting and pressed grits for relief designs. One of the greatest achievements of the last few years has been the development of automated techniques for decorating curved pieces.

Water-jet cut pieces
The technology for cutting ceramic tiles with water reached its greatest peak a decade ago. The technique consists basically of using high-pressure water jets to cut the ceramic pieces once they have been fired. Cutting can thus be extremely precise and the system also enables beautiful designs to be created.

The lines of the designs being executed by this technique are tending now to be increasingly simple.

The technique of shaping by casting or by using slip barbotine, which is used to create round-bodied pieces should also be mentioned.

The latest trends in special pieces
The latest decorative trends include combining other materials such as resins, metals, glass and so on with ceramic to demonstrate the versatility of ceramic tiles and ceramic's huge decorative potential.

Very schematic, geometric designs that draw upon those of the 1960's and 70's and are occasionally inspired by "Op Art" are also appearing.

As for rustic styles, ornamental motifs are generally being simplified. Drawings based on nature are fashionable but are being executed in a minimalist way. Series and collections with natural motifs in relief or that imitate vegetable and animal imprints in the purest style of fossils are becoming widespread.