Ceramics - How it's made | Ceramic Tiles

FLOOR TILES AND MORE PARTICULARLY MOSAICS 

At this stage of our process, when the firing of green ware has just been completed, we come upon the essential difference between wall tile and floor tile manufacture – that whereas wall tiles have still to be glazed, floor tiles have already become substantially a finished product, since they have only to be graded (some will be sold as "seconds," and some – those with anything like serious defects – will be destroyed) and "sized" (of "sizing" we shall speak later) and they are ready for dispatch to customers. 

Mosaic, however, although essentially the same as floor tiles from the manufacturing point of view, is not in the same position as its larger relatives in regard to marketing: for whereas floor tiles are sold loose, mosaic is commonly sent out, strange though this may appear to the unitiated, mounted on paper. 

Assembling geometrical mosaic

The mounting or assembling process is a fascinating one, whether the mosaic to be built up is of geometrical character or of the freehand type known as "Roman" mosaic. In the former the work is done with the help of an assembling frame. This consists of a flat board measuring about two feet by one, cut up into geometrical figures, such as hexagons or squares, by thin metal strips embedded edgewise in, and projecting slightly from, its surface. A quantity of mosaic tablets of the required size and shape having been heaped on to it, the frame is shaken smartly for a few seconds, when most of the tesserae or tablets fall into position in the spaces outlined by the strips. Any spaces left vacant are filled, and any new colour needed is introduced, by hand. That done, a sheet of stout paper treated with special adhesive paste is pressed on to the mosaic. A flat board is then placed over the paper, and frame, mosaic, and board are carefully turned over together. Finally the frame is lifted off, and the mosaic, now lying papered side downwards on the board, is left to dry. 

Building up a sanctuary floor in Roman mosaic

The assembling of Roman mosaic is necessarily of a less mechanical nature. Here the complete design to be built up is accurately drawn, and the colours to be used indicated, on one or more large sheets of stout mounting paper. The artists' work completed, this paper is cut up into small sections of a size suitable for handling, each section being numbered in accordance with a prepared key plan. The sections are then given to skilled mosaic workers, who faithfully build up the design in mosaic material, of which they paste in position small cut pieces of the size, shape, and colour called for by the design. In this way surprisingly beautiful work is done. 

Checking a large mural mosaic prior to despatch

 

The fixing of mounted mosaic, whether Geometrical or Roman, is a simple and a fairly rapid process. The fixer prepares the usual bed of cement and sand, presses the mosaic, paper side upwards, firmly into it and allows an hour or two for the cement to harden. He then carefully lifts of the now wet paper and thereby reveals the pattern, finishing his work by going over it with a "grouting" cement or mixtrure to fill in the joints. It need hardly be said that mosaic prepared and fixed in the manner described costs far less than that built up in situ by the laborious piecemeal method formerly employed. 

Before leaving this subject we may remark that mosaic, though more generally used for floors, is applied also to walls. This is perhaps more particularly true of Roman mosaic in which we have carried out many very rich designs, including a great deal of church work, for the adornment of walls as welI as floors. A small amount of glazed Roman mosaic (built up from cut pieces of glazed tile, gold glass, 
etc.) is also used. especially for decorative strips in coloured wall tiling. 

 

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From: "A Century of Progress 1837-1937" a publication to commemorate The Centenary of Richards Tiles Ltd.