Old
things, just like old people, need looking after if they are to survive.
Objects that have lasted for centuries may not last much longer if they are not
treated with care and respect and protected from the threats that can cause
damage.
The
following factors are important elements in what can be called “preventive
conservation”. Not every factor applies equally to every type of antique, but,
for a general collector, they all have a role to play.
Relative
Humidity
This
is a major factor that hastens decay and deterioration in all sorts of
materials, whether in a compost heap or a museum. Relative humidity refers to
the wetness or dryness of the air surrounding an object, there being a safe
range within which deterioration is halted or slowed. Some items are very
sensitive to humidity, such as books that can show “foxing” or brown marks when
exposed to damp, or wooden items that can disintegrate if allowed to get too
dry.
A
hygrometer can be used to measure relative humidity, and the values adjusted by
changing the temperature or by using a humidifier or dehumidifier to add or
remove moisture from the atmosphere in which the antique items are kept. As
well as the actual value of the relative humidity, sudden change is another
destructive factor, so any such adjustments should be made with care.
In
museums, relative humidity can be controlled item by item, if each is enclosed
in its own glass cabinet. However, this is not so easy to achieve in the home,
so it might be desirable to keep antiques that require different relative
humidities in separate rooms.
Water
Direct
contact with water can come about as the result of flooding, which would have
most relevance to furniture items. If there is a risk of flooding to a room,
such as in a house near a river, for example, valuable items can sometimes be
mounted on blocks that would keep them raised above likely flood levels.
Alternatively, keeping such items in upstairs rooms might be advisable.
Another
problem is spillage on wooden furniture, resulting in bloom or ring marking.
Prevention is definitely better than cure in such cases, so placing flower
vases on top of valuable pieces, for example, is to be avoided.
If
water is to be used when cleaning an item, it is best to test the effects in an
inconspicuous area before proceeding further, because water can dissolve
adhesives, dyes, paints, etc.
Light
Excessive
light can damage antique items, such as furniture or paintings, by causing
fading or colour changes. It can also lead to deterioration in fabric items
such as clothing, tapestries or book bindings. The damage is caused by the
brightness or intensity of the light, such as through south-facing windows (in
the Northern Hemisphere) and also by ultraviolet light, which cannot be seen
but is just as destructive.
A
lux meter can be used to measure the absolute amount of light entering a room,
with this being controlled by the use of filters, dimmers, and so on. The
positioning of light sources in a room is also important, so that bright light
does not fall directly on to the objects. Ultraviolet light can be controlled
by avoiding the use of fluorescent lighting, although sunlight also has a high
UV content.
Insects
and mould
Organic
materials are excellent insect food and also for the growth of moulds, if the
conditions are right. Moths do not damage fabrics, but their larvae do.
Likewise, the larvae of the furniture beetle, commonly known as woodworm, make
no distinction between floorboards and valuable pieces of Chippendale. Other
pests include the carpet beetle and fur beetle and, in some parts of the world,
termites.
Getting
the relative humidity right, and making sure that ventilation is adequate,
should prevent moulds and fungal growths forming. If there is a problem, the
important thing is to dry out the atmosphere gradually and increase the level
of ventilation. Fungicides should be used with care.
Insecticides
should be used with great care, as they can also cause damage to the items you
are trying to protect. It is better to examine objects carefully and regularly
for signs of attack and deal with small problems rather than large ones.
Heat
As
well as its role in relative humidity, mentioned above, excessive heat or cold
can have a direct impact on antique objects, and should be avoided. For example,
resins and waxes can melt, and paint can blister.
Dust
and pollution
Keeping
antiques dust free is not only important aesthetically but also in terms of
preventing deterioration, because dust can attract moisture and chemical
pollutants such as sulphides that tarnish silver and also form sulphuric acid.
Dust can also act as an abrasive that weakens textile fibres.
The
use of dust sheets and plastic coverings can prevent dust from reaching
valuable objects, although this makes it less easy to appreciate the beauty of
one’s antiques! Acid-free tissues can be used to advantage when cleaning.
Abrasion
and over-cleaning
Despite
the above note about the value of keeping items dust-free, it is also possible
to overdo the cleaning and polishing of antique items. For example, the value
of a piece of silver will be greatly reduced if the hallmarks are rendered
unreadable by over-zealous polishing, and the loss of fine detail will in any
case detract from the appeal of the item as a whole.
The
use of abrasive cleaning materials can cause scratching, and, for many antique
items, the patina of dirt acquired over centuries is part of their
attractiveness and should not be removed.
Cleaning
must therefore be done with great care, only using mild cleaning agents and
gentle pressure. The whole point of owning an antique object is that it does
NOT look like new!
Handling
and storage
The
more that fragile items such as glass or porcelain are moved or handled, the
greater their chance or being dropped. Excessive handling can also cause
finger-marks which could in turn attract mould. The leather bindings of books
can be damaged when pulled from a shelf, and ancient manuscripts should only be
touched when wearing soft gloves.
Likewise,
an antique’s safety may depend on how secure the surface is on which it is
displayed. The top of a wobbly bookcase is probably not the best place for your
priceless Ming vase!
Items
in storage are also not safe from deterioration if the conditions of storage
are incorrect. For example, an attic is quite likely to suffer from extremes of
heat and cold or to be damp. Materials in which items are wrapped can also have
an adverse effect, as such things as newspaper or foam rubber can release
harmful chemicals when they deteriorate.
With
all these factors to bear in mind, it sounds as though collecting antiques is
an activity that is fraught with peril! However, the responsible collector
appreciates that he or she holds these items on trust for future generations,
and has a duty to posterity to ensure that they are preserved as carefully as
possible.
That
said, the above precautions should not be too arduous to take, and, as said
earlier, not every hazard applies to every type of antique. It does, however,
behove the collector to be aware of the threats that apply to the objects he or
she wishes to collect, and to act accordingly.
© John Welford