Valuable antique pottery - such as Meissen, Sèvres and Chelsea (which date from the 18th century) - is too rare and delicate to be restored by anyone other than an expert. However, many other pieces of antique china, which probably have more charm than value, can be restored by anyone prepared to take the time.
Wash china in warm soapy water, then rinse and dry. Most domestic stains can be shifted by, rubbing with bicarbonate of soda or common salt. Grease and dust collects in cracks. Bleach with cotton wool pads soaked in hydrogen peroxide. Coarse antique china is porous and often stains badly, but it can be cleaned by soaking for up to a week in neat domestic bleach. In some cases, old joins may have to be taken apart. To soften glue, soak in boiling water and detergent. Methylated spirits, amyl acetate and acetone are other softeners that can be tried, but remember that complete immersion softens all joints. In the last resort, pick away at old adhesive with a needle.
Broken surfaces must be clean and fit exactly or they will not join properly. Wipe with a piece of silk dipped in methylated spirits. Silk will not leave lint on jagged edges. Put the thinnest possible coat of epoxy resin on each surface and press together. Remove any surplus adhesive before it dries, with a watercolour brush dipped in methylated spirits. Avoid touching the actual crack: any surplus on that must be removed by breaking the surface with fine glass-paper then by cutting it away with a razor blade. To make a really good join of smooth surfaces, such as those on antique plates or cups, apply pressure by clamping or putting weight on where possible, or by binding with a 1 ½ in. (40mm) wide brown paper gummed strip (but not self-adhesive tape). Gummed strips shrink as they dry and exert tension. Put the strips that are wet, but not dripping, at right angles across the join: it is pointless to fix a strip along the line of the join. When the join has set, soak off the strips and remove the surplus adhesive with glass-paper and a razor blade.
To repair an antique figure, bury it in a bowl of sand, with the broken surface just protruding and horizontal. Set it up so that the broken piece balances perfectly on its matching surface without adhesive. Glue it and keep checking to make sure that nothing slips. When the adhesive has set, remove any surplus along the join with fine glass-paper and a razor blade.
Chips can be filled with a mixture of epoxy resin and finely powdered chalk, called whiting. Missing parts on antique ornamental pieces can be replaced by modelling a new part out of epoxy resin filler. If the missing part - of a plate, for example - is flat, make a backing of a gummed strip. If the surface is curved, back it with dental impression compound, which can be bought from a dental materials supplier or from a dental mechanic. Mix a stiff-dough of epoxy resin with whiting and build it up against the backing. It sticks to the edges and, when dry, resembles unglazed china.
If the shape of the missing piece is part of a repetitive pattern, make a mould of a similar unbroken part with dental impression compound. Use this mould to make a new piece with quick drying filler. These pieces have to be cut and filed to fit when dry and stuck into place. Note that large missing pieces have to be cast. Model the missing part in plasticine. Use callipers to check the length and thickness of similar parts. Build up a square of plasticine strips on a sheet of glass. Insert a wooden peg through one side of the square and into the model to hold it horizontally above the glass in the middle of the square. Mix plaster of Paris and water in a bowl, stirring until the mixture resembles a thick cream and, pour into the mould until it is halfway up the model. Leave it to set. Cut two wide grooves in the plaster as locating marks when the two sections are joined. Coat the surfaces of the plaster with silicone grease and, fill the rest of the frame with fresh plaster. When it has set, remove the plasticine wall, ease the two sections apart and take out the model. This leaves a mould in which to cast the new piece with filler.
