Decorative Techniques
Decoration can be applied to pottery at various stages of making.
Decoration at the leather hard stage - (before firing)
- Slip Trailing - liquid clay, usually in a contrasting colour to the base pot is applied using a slip trailer (a bulb with a spout) to form dot or line patterns rather like clay icing. Marbled effects can be produced by mingling different coloured slips.
- Mocha - a dark acid mix is applied a drop at a time to a white alkali slip. The dark mocha spreads out in tree like patterns.
- Sgraffito - A contrasting slip is applied all over the pot, and then patterns are scratched in prior to firing.
- Incised Decoration - simple decoration cut into leather hard ware.
- Impressed Decoration - designs produced by pressing tools onto the surface of the clay. An embossing wheel or roulette can be used to produce a regular pattern around a pot.
- Pierced Decoration - shaped pieces of clay are removed from the ware using a sharp knife or by pressing a metal die into the clay.
- Sprigging - small moulds are made by engraving designs into metal or plaster. The mould is filled with clay and pressed onto the side of the ware. When the mould is removed the clay remains on the ware.
- Ornamenting - The disadvantage of sprigging is that the mould tends to leave pressure marks on the body of the ware. This can be avoided by relief ornamenting. A leather covered mallet is used to force clay into moulds. Excess clay is then cleaned off with a knife. The figure is carefully removed from the mould with a metal spatula, and applied to the semi-dry surface of the ware. This is the method used in Wedgwood's Jasperware.
Decoration after firing
- Glazing - a variety of coloured glaze effects can be used as decoration.
- Onglaze painting - metal oxides are painted onto the fired glaze using fat oil and turpentine as mediums. A low temperature firing (750 C) fixes the colours.
- Transfers - transferred patterns printed from engraved metal plates were once the most popular form of decorating in the pottery industry. Modern transfers are normally printed by lithography. A paper backing is peeled off by floating it in water and the transfer is slid into place on the glazed ware. A low temperature firing (700-800 C) fixes the colour.
- Gilding - applying gold as decoration. This is done by skilled gilders who apply the gold with fine brushes. Two types of gold are used. Best gold - best quality gold is mixed with mercury, after application it is fired to 730 C and is burnished (polished with a chamois and silver sand) to produce a bright finish). Bright gold is applied more thinly so is cheaper but it tends to rub off the ware more easily.
Decorating Bibliography
Hints on Fine Art Pottery Painting, C J S, Souter Sons and Co, Edinburgh, 1881.
D Skinner, The Art of the China PainterCity Museum and Art Gallery, Hanley.
Sheila Southwell, Painting China and Porcelain, Blanford Press, Dorset, 1980.
Kenneth Shaw,Ceramic Colours and Pottery DecorationMaclaren & Sons Ltd, London, 1962.
H G Clarke, Colour Printed Pictures of the Nineteenth Century on Staffordshire Pottery, Courier Press, 1924.
R Hainbach, Pottery Decorating, Scott Greenwood & Son, 1907.
William Turner, Transfer printing on Enamels, Porcelain and Pottery, Chapman & Hall Ltd, 1975.
William Ruscoe, A Manual for the Potter, Alec Tiranti Ltd, London , 1948.
Albert Kosloff, Screen Printing Techniques, Signs of the Times Publishing Company, 1975.
Bernard Leach, A Potters Book, Faber & Faber, 1976.
Muriel Rose, Artist Potters in England, Faber & Faber.
