Caring for Antiques
Carelessness, ignorance and neglect are the main causes of damage to antiques & collectables; value and craftsmanship can be ruined by over-zealous cleaning or misguided treatment
The ideal conditions for preserving fragile and precious objects are not necessarily the most comfortable for people to live in. But it is possible to strike a balance and the care and preservation of antiques is often simply a matter of common sense, good housekeeping, and understanding how different materials can be affected by heat, light, humidity and pollution.
Organic materials, for instance – those made from once-living matter, such as paper, leather and wood – are more sensitive to their environment that stone, ceramics, metals and glass. Objects made from a variety of different materials need to be treated with the most vulnerable material in mind.
All light ultimately destroys organic materials; it fades colours, breaks down fibres and alters the chemical make-up. The most harmful component in the light is the ultraviolet (UV) wavelengths. UV free lights and UV filters for fluorescent tubes are available from specialist lighting suppliers. Other barriers against ultra-violet, such as self adhesive film or spray-on varnish, can be applied to windows which are not leaded, of stained glass or prone to condensation. If you are having double glazing installed, you could consider glass which excludes UV rays.
Long exposure to weak light is as damaging as strong light for a shorter period. Where strong daylight streams in through windows during the day, ensure that there are no vulnerable items in its path. Blinds and net curtains have a filtering effect on strong daylight, and curtains can be drawn when a room is not in use during the day. Infrared rays from ordinary, incandescent bulbs radiate dehydrating heat, and are harmful if allowed to spotlight a work of art or build up in the enclosed space of a display cabinet. It may be better to light a display from outside the cabinet rather than within it Fibre-optic lamps with adjustable levels of light and cool beams are available, but are very expensive.
Temperature and Humidity
Temperature and humidity together or individually can cause materials to expand or contract. Organic materials readily absorb moisture in a damp environment and so expand, and release moisture in a dry atmosphere and so contract. Such movements can lead to wood warping, splitting and cracking. In a damp atmosphere too, tarnishing and corrosion of metals is more rapid. The ideal ‘museum’ level of relative humidity for antiques is around 55%, which is a perfectly acceptable level for living in, although a centrally heated home may be on the dry side at 40-45%. You can check humidity levels with humidity indicator cards or strips with a simple hygrometer, available from garden shops. Humidifying and dehumidifying devices range from simple gadgets which clip onto radiators to expensive, freestanding electric models. Beware; however, as warmth combined with over 60-65% humidity provides ideal conditions for mould spoors to germinate and for wood to warp.
An atmosphere that fluctuates between extremes of temperature and humidity is most damaging of all. A piece of furniture for example, which has been in a cold damp house for generations, will have adjusted to its environment. But if it were suddenly to be moved to a warm, centrally heated room, it would warp and crack, and veneered surfaces might peel away from the carcass. So aim for as constant a temperature as possible. The central heating, for example, could be kept on low at night and not set too high during waking hours. Keep rooms well aired and vulnerable items away from condensation, steam, direct heat from radiators or lights, or chilly walls against the outside of the house.
Car exhaust fumes, factory emissions and burning fossil fuels produce a greasy film of fine dust, and gases which combine with moisture to form acids in the atmosphere. These can slowly eat away at vulnerable materials such as textiles. Destructive substances within the house include acetic acid in the form of vinegar and vapours from freshly painted rooms. Formaldehyde is given off by some composite woods like chipboard and acts as a corrosive itself or causes destructive reactions in other materials. Air conditioning and glass or Perspex-fronted display cabinets provide protection but are not usually necessary. General awareness of the problems should suffice: ventilate rooms well if they have been filled with smoke from open fires or candles, and if you live in a town keep sensitive, unprotected articles away from open windows.
Vermin and Insects
Rats, mice, woodworm and other beetles, moths, silverfish, thrips and thunderflies are among the creatures that invade northern European homes. Commercial insecticides and pest repellents may be effective, but may also damage the piece you are trying to protect Preventative measures such as regular close inspection – every year for books and textiles, twice a year for furniture – is the best defence, so that a problem is identified before too much damage is done. If any pieces are infested, isolate them from other furniture to halt the spread of insect larvae, and seek expert advice.
Few of us can afford to take every damaged object to a conservator (conservation expert). But with antiques, never leap recklessly into home repair; you could damage a piece irretrievably and destroy its value. A home repair is unlikely to be the ‘invisible mend’ a specialist could achieve, and you may find that your handiwork needs to be undone, in a far more involved and expensive professional repair later on. If you do make a temporary repair, be certain of the type of material you are dealing with and its vulnerabilities, and make sure the repair is reversible - by using water- soluble glue, for example.
Some antiques are worth more unrepaired than repaired, even if the work is done by a professional. If in doubt, consult the conservation department of a major auction house or museum before any repair or major restoration. Take a clear photograph of any valuable object when you first acquire it; if it is subsequently broken, this could provide useful reference for the conservator.
A recommendation- from a friend, a trusted dealer, a local or national museum, or the conservation department of a major auction house – is the best starting point for finding a reliable restorer. The Museums and Galleries Commission, the United Kingdom Institute for Conservation, and conservation training institutions such as the Courtauld are also useful sources. Look for a specialist conservator or a large workshop that employs specialists. Ask what materials and methods are going to be used for the job – if it is suggested that a veneer is to be glued with epoxy resin rather than reversible animal glue, find another conservator. The cost of restoration depends mainly on how long the repair will take , plus cost of materials and VAT It bears no relation to the value of a piece; as a paper conservator commented ‘whether a print is worth £20 or £10,000, we treat it in the same way and charge the same rate’.
Get a written estimate of the cost and completion date. Check whether delivery is included in the price. When the piece is handed over to the conservator, get a receipt and check who is responsible for insurance during restoration. On completion, ask for the details of restoration to be included on the receipt. Keep this as a record.
Antique furniture is rarely kept solely for display purposes, but certain precautions are necessary if it is to withstand daily wear and tear.
Treat your antique furniture with respect for its original purpose. The surface of an old desk, for example, was not designed to withstand the pressure of a ballpoint pen Tilting back on a chair, opening a drawer by only one of the handles, dragging furniture rather than lifting it, all put unnecessary strain on the structure. Before lifting furniture, empty any contents and remove detachable parts for carrying separately. Take hold of the lower part of the main frame – not, for example, the top surface of a table – and pick up chairs under the seat
A surface patina, even if it is marked and damaged, contributes to the character, authenticity and character, authenticity and value of a piece of furniture and the aim should be to preserve it. If restoration is necessary, the original finish should be matched at closely as possible. French polishing or the tough synthetic varnishes of the 20th century should never, for example, be used to replace wax or shellac.
Oil or beeswax polishes are the most common finished on 16th and 17th century furniture, and on oak and country furniture to the 19th century; they are more resistant to minor bruises and spills than varnish or lacquer. Resin and shellac varnishes came to be used on fine furniture from the end of the 17th century. Like lacquered and japanned finishes, these are spirit-based, and so can be marked by other solvents such as alcohol, as well as by wet, damp and abrasives. French polishing, introduced in the early 1820s, is a method of applying shellac that a achieved a high-gloss finish with less effort but is less durable and prone to chip. Newly applied French polish is particularly vulnerable, it can take up to six months to harden completely.
Other finishes include graining and ebonising, in which a surface is stained to resemble an exotic wood; this effect will wear away with too much rubbing.
Veneered furniture is particularly vulnerable to dry or damp conditions, or if water polish seeps beneath the surface skin, causing the veneer to buckle, lift or split. Inlaid finishes such as marquetry and boulle are even more sensitive as the various materials used react to heat and humidity at different rates, resulting in uneven stress over the surface as a whole.
Dusting And Cleaning
Frequent dusting is important, especially on a waxed surface which is soft and absorbs dirst, and especially before cleaning or polishing as particles of dust are abrasive. Use a clean dry duster with no frayed edges (which could catch) for most jobs, but for any surface that has begun to lift or crack, use a soft bristled brush (also handy for crevices). Check that no grit is lodged in the brush, and cover sharp edges with masking tape. Feather dusters are to be avoided as the feathers break and the spines could scratch a delicate surface.
Spot-test any inconspicuous part of a piece of furniture before trying any cleaning medium. No fluids should be used to clean porous materials such as mother of pearl or ivory, or damaged lacquered, painted or veneered surfaces. A sound waxed or lacquer surface can be cleaned with a soft, damp cloth (add a tablespoonful of non-ionic detergent to a washing-up bowl of warm water). Wipe the surface with a clean cloth rinsed and wrung out in clear water and dry immediately with absorbent paper. Never use detergent on bare, unpolished or damaged wood surfaces where it might penetrate and stain.
If spillages are dealt with immediately, they are unlikely to harm a sound wax or lacquered surface. Candlewax may lift off easily in a slab when cold, or can be warmed with a hot-water bottle wrapped in a clean cloth and then scraped off with a fingernail or orange stick. Deeply ingrained stains should be left for an expert to deal with, or left to contribute to the character of the piece. You can try treating the whitish marks left by the damp base of a glass, for example, by wiping with a little metal polish, if the surface finish is not delicate and as long as it is wiped clean with a damp cloth and dried immediately.
All sealed wooden surfaces can be waxed to bring out the colour and grain of the wood and to provide protection against staining. But overwaxing will actually cause dullness. Furniture that has been waxed and polished over the years should only need buffing with a soft chamois leather or duster, and a waxing maybe once every few months. We recommend David Harper's Fabulous Furniture Wax Polish!
Some solvents used in furniture polishes, especially the spray-on types, may leave a whitist bloom on some surfaces or gradually dissolve lacquered finishes. They should not be used on any lacquered surface and only sparingly on wax. A microcrystalline wax is the best medium for giving light, protective and burnishable coating to most surfaces, including ebonised wood, lacquer and French polish. Apply the wax over an area about 1ft (30cm) square at a time, burnishing with a soft, clean cloth as it dries. Use a soft-bristled brush for carved surfaces, leaving no surplus polish in the crevices.
Brass mounts, such as handles and other fittings, do not need to be ultra-bright on antique furniture; light burnishing as you dust should be adequate, or buff with a long-term silver cloth. Metal cleaners should not be used as they can harm the wood around them.
The gold finish on ormolu is very delicate and should never be polished, even with a dry cloth, and especially not with cleaning fluid. Even fingerprints, which are acidic, can damage gildings. In time the brass or bronze base corrodes, giving the finish a spotty, then black appearance. The mounts can be lacquered but even this will fail in time. Other than dusting ormolu gently and regularly with a soft brush there is little else to do; never have it regilded if you want to retain the value.
Caring for Gilded Surfaces
Water-based gilding remains water soluble and should only ever be dusted, whereas oil gilding may be cleaned by gently dabbing with barely moistened cotton wool. Water gilding is applied over layers of gesso and a yellow or dark red size, and may be burnished to a high shine, although some areas may be left matt. Oil gilding is sometimes applies directly into wood and has a matt finish. Chips in a gilded surface can be filled with a fine surface filler and disguised with yellow ochre watercolour paint. Avoid using ‘gold’ metallic paint for areas of any size, as it clashes with the true gilding. A professional gilder’s aim is to match the original techniques and materials, and to retain as much of the original surface and patina as possible.
Dealing With Woodworm
Adult furniture and pinhole beetles lay eggs in crevices in wood. The eggs hatch into larvae (woodworm) which each into the wood, leaving tunnels some 1mm in diameter, before they emerge as beetles and fly away, usually between May and August. Active infestation is revealed by freshly bored holes and deposits of sawdust or ‘frass’.
Check –and treat-any new purchase before you take it into the home, and check all wooden objects twice a year for infestation-especially bare and softwood surfaces such as the insides of drawers and backboards. Upholstered or particularly delicate furniture should be professionally fumigated, but on other items, a good quality, clear, low-odour woodworm fluid can be applied at home.
The most effective time for treatment is late spring or early summer. Remove any detachable upholstered parts and only treat the unfinished surfaces of wood-solvent in the fluid will damage waxed, polished, varnished, lacquered or painted surfaces. Carefully paint on the insecticide. Injecting insecticide, using a hypodermic syringe and needle to reach deep into the holes, should be left to an expert. Following treatment, fill the holes with soft wax to blend in with the surrounding wood.
Unlike many other antiques, which may be devalued by restoration, a piece of furniture which has been sympathetically and honestly restored into useable condition, using traditional methods and materials, can be worth more than a damaged item. If you do make minor repairs yourself, only ever use water soluble wood glue.
Almost all furniture made before the mid 20th century depends on well-jointed solid timber for strength , so weaknesses in joints, pivots, moving parts, or on load-bearing surfaces, or signs of rot or woodworm must be fixed before the piece is used again. A restorer can reinforce or replace rotten or wormed timber with sound wood, saturate it with resin or fill it with a mixture of animal glue and sawdust. Sticking doors or drawers may be eased by a touch of candle wax, but if they are misshapen, they need to be trimmed by an expert. Chipped or lifted veneer should be professionally repaired as soon as possible, but exposed edges can be temporarily protected with masking tape and detached pieces kept in a plastic bag.
If stripping is necessary and will not remove a valuable patina, it should be done by a furniture conservator. Acid stripping swells and rots wood fibres.
Dry cracked leather on desk-tops (and bookbinding) can be revitalised with a lanolin and beeswax preparation such as Connolly’s Hide Food. Spot-test the dressing on an inconspicuous area; if it leaves no stain, then apply it sparingly with a soft cloth. Let the dressing absorb (about 24 hours) before gently buffing with a clean duster.
Upholstered furniture must be vacuumed regularly to guard against a build-up of dust and pests, if necessary using a net of fine-meshed stocking over the nozzle of the vacuum cleaner to prevent any loose pieces being irretrievably sucked off.
Fine, old upholstery fabric should be reserved for display only, although a loose cover can offer some protection. However, on some seat furniture, upholstery can be rewebbed or restuffed, or the fabric replaced with a sympathetic alternative, without detracting from the value of the piece – but seek expert advice first. Do make sure that newly re-upholstered drop-in seats are returned to the correct chair, and that and new covering is not so tightly fitting that it strains the leg joints.
Source: 'Treasures in your Home' Reader's Digest