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07 31st, 2009| 
COINS AND MEDALS
Coins should not be cleaned unless it is absolutely necessary. They loose a lot of value through faulty cleaning, and it is just as important to know when to clean as to know how. Get a book out of your library on coin collecting and study it before cleaning any coins, if you know little of the subject.
Gold Coins. Wash very dirty coins in soap and water using a stiff bristled brush very carefully. Dry gold coins with a soft cloth or soft leather.
Silver Coins. If silver coins are not in exceptionally good condition and arc rather worn, removing the ingrained dirt will often make them look a lot worse! If they are tarnished to a blue or green colour, this gets damaged by too much washing and brushing up, and most collectors prefer to leave well alone. Silver coins which arc in really good condition but have uneven toning or are just plain filthy, should be treated either with carbon tetrachloride or trichlorethylene (see Solvent_). This is dabbed (not rubbed) on very gently, and immediately afterwards the coins are washed in running water. On really ugly toning use Goddard’s Silver Dip but do not wash the coins afterwards or they will look too highly polished. Don’t rub coins with the polishing cloths provided with cleaners. Ammonia in ten per cent solution will also remove stains, the coins being washed immediately after application; otherwise a whitish skin will appear which will ruin all your careful work.
Copper coins. Verdigris on copper coins is often caused by cigarette ash dropping on to them, and although this is hard to remove it can sometimes be done by soaking the bad part iun olive oil and scratching the verdigris off with a bone needle. Don’t use steel needles for they scratch the surface of the coin. Don’t use solvents on copper coins, just clean them with a stiff bristle brush used quite dry.
Copper, silver and bronze coins and medals can also be cleaned by immersion for a very short time in a solution of five per cent nitric acid. Do this with great care for the acid will etch metal, particularly copper. Take the pieces out after one or two seconds and wash them immediately under a running tap. If only a part of the coin is corroded, protect the rest of it from the acid with a coat of wax or grease before immersion in the acid, and then wash it thoroughly. Polish coins with a little lanolin grease or Renaissance wax polish. I
DETERGENTS
Detergents are the modern substitute for soap, and are perfectly suitable for many cleaning jobs as they so readily remove greasy dirt. However, some of the commercial brands sold as washing powders, or as liquid washers, have added ingredients of some kind : scent, colour or ‘whiteners’. While clung, glass and pottery can be cleaned quite safely with these, they are often not suitable for cleaning other Materials, and where detergent is recommended it is best to use a pure detergent such as the following:
Teepol
Boots Liquor Sulphestrol Lissapol N.
Detergent can be mixed with other chemicals to make an emulsion which will spread and penetrate easier that way-for instance carbon tetrachloride and benzene mixed with one per cent Lissapol N for cleaning some kinds of stonework.
ENAMEL
Enamel is a type of glass with added colours in the form of metallic oxides. This is fused to the surface of metal objects.
Enamel on metal may be of three different types: painted on to an enamelbackground; Cloisorui6, which is done by soldering fine wire to the metal surface to shape the designs, and then infilling with enamel; or Clianipl8ve where the
same effect is achieved by cutting shallow cells into the
surface of die metal to take the enamel. In atypes, an
object is then fired to fuse the glass and enamel.
Enamels should be kept away from direct heat, as the glass will expand at a different rate from its metal base and stresses will be set up which may result in the enamel lifting or crazing. Enamel on metal which doesn’t like damp, such as copper, must be kept dry otherwise corrosion may form on the metal and lift the enamel.
To restore enamels, use ordinary artist’s oil colours, and where chunks are broken off, a good imitation can be made by adding colour to Araldite, or to a thick solution of celluloid in amyl acetate, or to Durofix.
Having retouched the colour, enamelled objects can then be lacquered with Frigilene, or painted with thin acrylic, which will reseal any lifting pieces. Once the lacquer has soaked right in and dried, so that it has filled any cracks and cemented down loose pieces, wipe the surface of the enamel very carefully with a piece of cotton wool wrung out in acetone. Be careful that no liquid acetone runs into joins etc., or it will undo the repair work that has just been done. If enamel has at some time been repaired with animal glue, it may have gone slightly mouldy. Wipe the joins with Santobrite before continuing with retouching and lacquering.
Don’t try to refire enamel, it just won’t work.
FABRICS
All textiles come wider this heading, and generally the cleaning treatments depend upon whether dyes have been used or whether the fabric has simply been bleached or whitened. Cotton and linen have usually been bleached, and go very yellow with age. If the fabric is in good condition use very dilute domestic bleach to rewhiten it, then thoroughly rinse the article in several changes of clean water. Reckitt’s Blue may be added to the last rinse. Delicate articles made of muslin or lace, which are in a fragile state, cannot be given such rough treatment. A powdering of French chalk or Fuller’s Earth, later brushed off, will remove some stains and grease marks. If the article is attached to a cushion for instance, this may be the only way of dealing with it. Lace which can be detached should be placed in distilled water for a while to loosen the dirt, then put into fresh water containing a little pure liquid detergent and soaked again. Paddle it gently up and down in the water if the dirt is stubborn. After careful rinsing, spread the lace on to white blotting paper and pin it flat, and put it in a warm place to dry. It is important to pin lace properly in shape or it may distort during drying.
Muslin garments such as old doll’s clothes or old baby clothes are best washed very carefully in a mild solution of detergent, and should not be rubbed, but gently paddled up and down. It is most important to rinse the garment two or three dines in clean distilled or rain water. The garment should be rolled in absorbent paper and ironed
flat when it is nearly dry.
Coloured fabrics which are not colour fast can be cleaned with carbon tetrachloride. Heavy embossed material will be considerably brightened by brushing with a mixture of four parts benzol and one part methylated spirit.
Test for colour fastness by laying the fabric over white blotting paper, and then patting it carefully with a swab of damp cotton wool. If the colour runs it will show on the blotting paper underneath. If the material is old, the dyes are probably vegetable in origin, and likely to run, so should only be washed in cold water.
To remove large stains on this fabric, place the piece on clean blotting paper and then drop a solvent into the centre of the stain, which will spread out and go through on to the blotting paper carrying die stain with it.
To remove stains on textiles, provided the stain can be identified, try the following treatments, always with care and a minimum of rubbing.
Alcoholic Drinks: Wash in warm suds. Sponge with surgical or methylated spirit.
Beer: Soak in a hot solution of z teaspoonfuls of sodium sesquicarbonate (water softener) to z pints of water, and rinse out well.
Blood: Fresh stains. Soak immediately in a solution of i teaspoonful of salt and i teaspoonful ammonia to i pint of warm water. Then wash out in warm suds, and rinse. Old stains. Try soaking in ammonia solution, r tablespoonful to i pint of water.
Or try a solution of j teaspoonful of ammonia with i part of zo volume hydrogen peroxide with 4 parts of cold water.
Soak for just half an hour if the fabric is coloured, as long as necessary for white or colour fast materials.
On cottons and linens, but not on silks or wool, oxalic acid solution, 2 level teaspoonfuls of crystals in 2 pints of cold water, mixed in a china or glass container, can be dabbed on and removed by rinsing within ten minutes.
Silk or wool should be soaked in a solution of salt and water.
Coffee: If washing does not remove it, try hydrogen peroxide as for blood.
Cosmetics: Clean with carbon tetrachloride. Lipstick can sometimes be lifted from washable fabrics by smearing with vaseline and then washing in warm suds.
Egg Stains: If they won’t wash out, soak in a solution of salt and water, or try one of the proprietary digestive types of stain removers, such as Big S., Biotex or Radiant.
Fruit and Berry Stains: If they won’t wash out they can be removed by working a few drops of glycerine into the stain, leaving it overnight and then damping with a few drops of white vinegar, and then washing out with warm water after two minutes. Cherry, pear, peach, plum and other stubborn fruit stains in cotton or linen can be bleached out with hydrogen peroxide solution as for blood. Soak the stained spot for a few minutes and then wash it out in scsquicarbonate, J teaspoonful to I pint of water.
Glue: Must be removed with solvent. Acetone or nail varnish remover will probably shift it.
Grease: Such as butter or candlewaX. Wash in water with a little ammonia added. Put fabric under blotting papre and iron. Sponge with carbon tetrachloride.
Indelible Pencil: Sponge with methylated spirit.
hik: Ballpoint ink can be removed with methylated spirit. Indian ink must be sponged with methylatedspirit and then rubbed with glycerine. Repeat the treatment until the stain lifts and then wash with detergent and water. Old Indian ink stains are there for ever! Writing ink, the same treatment.
Mildew: This is difficult to remove. Washing thoroughly in sodium sesquicarbonate may help.
Nail Varnish: Remove with amyl acetate or nail varnish remover.
Paint: Emulsion paint; soften it from underneath with amyl acetate, then rub off, and work in a paste of soap and water and wash well. Oil paint, dried; carbon tetrachloride or benzene on the underside till the paint has softened, then wash out as above.
Rust and Ironiyiould: Try oxalic acid treatment as for blood. Rust remover can be used in extreme cases, but must be tried with care and washed out thoroughly.
Shellac: Soften with methylated spirit.
Shoe Polish: Bleach out with hydrogen peroxide.
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