| For aesthetic reasons articles can be | | | | as the primary decorating material on their |
| decorated by a large variety of techniques , | | | | ware. Sgraffito involves scratching through a |
| including the application of colours and | | | | layer of coloured slip to reveal a different |
| designs. Decoration can be: | | | | colour or the base clay underneath. If done |
| | | | carefully, one colour of slip can be fired |
| In the body | | | | before a second is applied prior to the |
| | | | scratching or incising decoration. Often |
| On the surface of the body but beneath the | | | | slips/engobes used in this process have a |
| glaze, underglaze decoration | | | | higher silica content, sometimes approaching |
| | | | a glaze recipe. This is particularly useful |
| In the glaze | | | | if the base clay is not of the desired colour |
| | | | or texture. |
| On the surface of the glaze, on-glaze | | | | |
| decoration | | | | Banding, is the application, by hand or by |
| | | | machine, of a band of colour to the edge of a |
| Additives can be worked into moist clay body, | | | | plate or cup. Also known as lining |
| prior to forming, to produce desired | | | | |
| characteristics to the finished ware. Various | | | | Litho, is a commonly used abbreviation for |
| coarse additives, such as sand and grog | | | | lithography although alternatives names of |
| (fired clay which has been finely ground) to | | | | transfer or decal or used. These are used to |
| give the final product texture, and | | | | apply designs to artciles. The litho |
| contrasting colored clays and grogs result in | | | | comprises three layers: the colour, or image, |
| patterns. Colorants, usually metal oxides and | | | | layer which comprises the decorative design; |
| carbonates, are added singly or in | | | | the covercoat, a clear protective layer, |
| combinations to achieve a desired colour. | | | | which may incorporate a low-melting glass; |
| Combustible particles can be mixed with the | | | | the backing paper on which the design is |
| body or pressed into the surface to produce | | | | printed by screen printing or lithography. |
| texture. | | | | There are various methods of transferring the |
| | | | design while removing the backing-paper, some |
| Agateware A long established technqiue is to | | | | of which are suited to machine application |
| partially mix different coloured clay bodies | | | | |
| to give a distinctive 'mottled' decoration. | | | | Gold, decoration with gold is used on some |
| In Great Britain, these techniques are known | | | | high quality ware. Different methods exist |
| as agateware, after agate stone which shows | | | | for its applications, including: |
| similar colour banding, whilst in Japan a | | | | |
| similar technqiue is called "neriage. An | | | | Best gold - a suspension of gold powder in |
| analogue of marquetry can also be made, by | | | | essential oils mixed with a flux and a |
| pressing small blocks of coloured clays | | | | mercury salt extended. This can be applied by |
| together, and using the resulting mosaic to | | | | a painting technique. From the kiln the |
| create distinctive patterns. To ensure the | | | | decoration is dull and requires burnishing is |
| final articles are unfaulted care is needed | | | | reveal the full colour |
| with selection to choice different bodies of | | | | |
| compatible shrinkage and thermal expansion | | | | Acid Gold – a form of gold decoration |
| | | | developed in the early 1860s at Mintons Ltd., |
| Burnishing, like the metalwork technique of | | | | Stoke-on-Trent, UK. The glazed surface is |
| the same name, involves rubbing the surface | | | | etched with dilute hydrofluoric acid prior to |
| of the unfired article with a suitable tool, | | | | application of the gold. The process demands |
| typically of wood, steel or stone, to give a | | | | great skill and is used for the decoration |
| smooth, polished surface which remains even | | | | only of ware of the highest class. |
| after firing. Finer clays give a smoother, | | | | |
| shinier surface than coarser clays, as will | | | | Bright Gold – consists of a solution |
| allowing the pot to dry more before | | | | of gold sulphoresinate together with other |
| burnishing although that risks breakage | | | | metal resinates and a flux. The name derives |
| | | | from the appearance of the decoration |
| An ancient Armenian urn.Engobe, to give a | | | | immediately after removal from the kiln as it |
| finer surface, or a coloured surface, slip | | | | requires no burnishing |
| can be coated onto the leather-dry body. Slip | | | | |
| produced to a specific recipe is sometimes | | | | Mussel Gold – an old method of gold |
| called an engobe. Slips or engobes can be | | | | decoration. It was made by rubbing together |
| applied by painting techniques, or the piece | | | | gold leaf, sugar and salt, followed by |
| can be dipped for a uniform coating. Many | | | | washing to remove solubles. |
| pre-historic and historic cultures used slip | | | | |