CHINA DECORATION. The decoration of china, and, indeed, of all kinds of clay wares, falls into two groups: (1) Controlled by method, and (2) controlled by producer. The former group deals with the fact that a decora tion can be introduced at any stage of the man ufacture; the latter concerns itself with the various handicrafts employed.
Decorations may be used under the glaze, either on the unburned or burned clay; in the glaze, as a natural coloring; on the glaze, after the hard-glaze fire.
Decorations on the clay usually take the form of sgraffito (incising) i inlaying, or pate or patnting with diluted clay. In the two latter it is important that the inlaid or over laid clay should be similar in composition to the main body, or the fire will cause them to sep arate. The body piece, formed either in a mold or upon the wheel. (see POTIF.RY Mann FACITTRE) , is kept quite damp, and the design, lightly sketched in India ink, is carefully followed. In inlaid work a channel is tooled out of the body, and filled in with clay of a different color. In pate no cutting out is necessary, but usually the background is stained a dark color and the design is laid on in white. The beautiful works of M. Solon are of this class.
On the burned ware under-glaze decoration may be either painted or printed. Most of the modern hotel and restaurant ware is printed under the glaze.
For some classes of work a coloring added to the glaze itself is very effective. By this means are produced the flowing and flashed effects much followed by the Japanese and by many French ceramists. In America the Ded ham Pottery has worked in this direction.
For work over the glaze a lower fire is em ployed, Many more colors are available, and the processes of decoration include painting, gilding, printing, and ground-laying.
Ceramic colors are made from certain me tallic oxides with which are blended a fusible flux, so that the mixture may melt and attach itself to the glaze. Various fluxes are in use. They are composed of red lead, borax and quartz sand in varying proportions. These in gredients are melted together, and the resulting glass is finely ground. For blues the oxide of
cobalt is, used; for greens, those of copper and chromium; for yellows, antimony and lead; for reds and browns, iron; for dark brown, manga nese; for grays, nickel and iridium. Gold produces rose color and purple, and a pink is also made from tin oxide and chromic acid. In some cases the colorant and the flux are melted together; sometimes they are united only in the grinding-mill. For under-glaze work, as well 'as for the coloring of clays and glazes, the list is not so full. Some of the oxides fail under the higher temperature, and must there fore be confined to over-glaze use.
In the second group. decoration is considered as a handicraft: Division of labor is the rule in a manufactory; and thus a piece of china may pass successively through the hands of the ground-layer, the painter, the printer and the gilder, together with those of many minor opera tors. To the ground-layer falls the task of dis tributing an even tint over the whole piece or upon some part of the design. Using a stiff oil, — linseed boiled with litharge or lead acetate,— he dilutes it with turpentine, and brushes a thin coating over the china. This coating he dabs with a soft linen pad, and then spreads the color, a fine dry powder. A certain quantity adheres to the oil, and a smooth tint is the result. If only part of a design is to be covered, the free portions are painted with a water-color mixed with molasses. The work is oiled and dusted as before, and is then immersed in water, when the water-color is washed up, taking with it any of the ground color which may have settled upon it.
The painting of china scarcely needs a de scription. The colors are as already explained, and the painting depends upon the personal skill put forth. The colors are mixed m turpentine and fat oil just as the painter pleases, for each artist mixes his own ,palette.• The colors change somewhat in the fire, but not 4s much as is often supposed. The main difference is a great gain of brilliance.