A decoration that is painted with under-glaze colors on top of an unfired opaque glaze is referred to as a Majolica decoration. The term “Majolica” originated many hundreds of years ago. During those early centuries most of the available clay was of a dark color which made decorating with brilliant colors difficult. Gradually the eastern potters learned that tin added to a transparent glaze would render it opaque, but tin was scarce. About the year 1500, many potters from the east, especially the Moors, were carrying their ware to the island of Majorca, off the coast of Spain, and since Spain was rich in tin, before long the potters added tin to their transparent glaze, producing a hard white opaque glaze. With this glaze covering the dark body of the clay, bright colors could be used effectively. The new ware was given the name “Majolica” and became very popular when it was brought into Italy. It is still used widely as a means of decorating ceramics.
Although today we are fortunate in having a wide selection of white clay bodies to choose from, thus eliminating the necessity of resorting to Majolica as the only means of decorating with bright colors, Majolica decoration possesses a charm that makes it attractive to modern-day ceramists. The effect derived from painting with under-glazes on top of the unfired glaze is totally different from that of an orthodox under-glaze decoration and the procedure is necessarily different too.
First glaze the ceramic piece with a white opaque glaze. Painting over a coat of unfired glaze is difficult, so give the glazed piece a light coat of gum tragacanth before attempting further decorating. Do not use a pencil to sketch the design on the piece because the point is likely to mar the glaze. Instead, brush the design on with diluted India ink or vegetable dye which will burn out completely during the firing and will, in addition, provide good practice for the brush work in the final design. Underglaze colors painted on top of an unfired glaze do not entirely fuse with the glaze when fired and often appear dull in contrast to the glaze’s sheen. To remedy this, add a small amount of transparent glaze to the underglaze colors so they will fire properly and shine with the glaze. The quality of the brush work is most important in Majolica decoration and glycerin or mineral oil used instead of water will make brushing easier. Because of the rough surface of the unfired glaze, a dry brush technique can be used to good advantage. Keep your decorating direct and free and avoid overworking your strokes. If
To begin a Majolica decoration, glaze the piece with white opaque glaze and coat it with gum tragacanth.
You can brush on a partial background with diluted underglaze colors.
you get a chance examine the Majolica ware from Italy; you will notice that the charm of the ware is derived largely from the freshness and colorful crispness of the decoration.
Sketch the design on the piece with diluted India ink, which will burn out during the firing.
Paint the design with dry brush strokes, a good technique to use on the rough surface of the unfired glaze. Make sure you have removed all excess color from the brush and do not go over your strokes or they will lose their effect
Add accents of black to complete the decoration, and fire.
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