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Stable or painted surfaces should be kept dust free. Vacuum clean all stable
statues regularly, using the nozzle attachment with a brush. A bristle brush,
or a toothbrush may help to raise dust from crevices.
Sometimes surface grime can be removed satisfactorily with soap and water.
We recommend a plain soap in a 3% solution in water. Use deionized or distilled
water, and rinsing is a very important step. If the dirt you want to remove
is very greasy, "Vulpex" may be used in mineral spirits, in a 3% solution;
rinse with straight mineral spirits. It is especially important to remove old
polish residues, which appear usually as dark green, gray or white deposits
in cracks.
Calcareous (lime or hard water) deposits may respond to a 10 % solution of
regular "Calgon" (sodium hexametaphosphate) in distilled or deionized
water. Allow the solution to soak into the crust and then remove by scrubbing
with stiff brushes. Then rinse thoroughly in distilled water.
Degreasing
The presence of degraded oils and grime may promote corrosion. You can degrease
most uncoated statues with mineral spirits. (Please consult the manufacturer
or Material Safety Data Sheet for complete safety requirements.) Wipe it over
the surface in a small, inconspicuous area first to test for discoloration.
After the solvent has evaporated, check for any undesirable effects (usually
caused by residual dust or an old finish). Continue the cleaning process, using
mineral spirits- dampened cloths to lift the grime. You may find that sharpened
bamboo skewers, nylon bristle "parts brushes", craft stencil brushes
or even tooth brushes help you to get into crevices and joined areas. If straight
mineral spirits does not seem to be raising the grime, a surfactant, "Vulpex",
may be used in a 1% solution in mineral spirits. Be very certain to rinse with
clean mineral spirits to remove residual detergent. This method is Not recommended
for old copper with richly patinated surface accumulations.
Corrosion removal
Very heavily corroded objects, like those unearthed or found in water, statues
with original painted surfaces or those damaged by salts may require the assistance
of a trained expert. By attempting to remove thick corrosion with steel wool
or other scrapers, you may end up scratching or abrading the metal surface.

Some bronze may have been polished to a bright finish, and altering original
surfaces may reduce the historical value of an object. As mentioned above, some
dark, stable surfaces may be considered "patinas." Collectors should
be aware of any special finishes, especially lacquers and patinas, which may
determine the correct color the metal should be, the degree to which it should
be cleaned and/or the degree to which it should be polished. If you come across
any special coating after you have cleaned off the simple dirt, you may wish
to consult with an expert before proceeding.
If you wish to return a bronze or brass object to its original, polished appearance,
it is usually possible with a fair amount of elbow grease and a good polishing
compound.
Old lacquers must be removed prior to polishing. If the lacquer is original
and in fairly good shape, you may consider investing in a professional treatment
to preserve it. Lacquer removal is best done with acetone, preferably by immersion.
Acetone is a volatile solvent that should never be used in a poorly ventilated
area. (Please consult the manufacturer or Material Safety Data Sheet for complete
safety requirements.)
Polishing with a mild abrasive is the only safe cleaning method recommend.
Copper and its alloys are relatively soft metals. Commercially available "dips"
may contain undesirable components such as hydrochloric or sulfuric acid which
act too quickly and remove more metal than simple polishing does.
Some commercial paste polishes are quite abrasive and may scratch your fine
metalwork. For statues not suffering from heavy corrosion "Duraglit Wadding"
polish may be somewhat less abrasive than others. Light polishing may be done
using jeweler's cloth containing rouge ( i.e. "Birk Cloth", "Hagerty
Glove"). A museum-proven, safe polishing method is as follows:
POLISHING METHOD 1
For most polishing use fine calcium carbonate, CHALK, ("whiting")
worked into a slurry or runny paste with equal amounts of ethanol (denatured
alcohol, ethyl alcohol) and distilled water. The paste is rubbed across the
surface, working a small area at a time, with cotton balls or clean cotton rags.
Detailed areas may be polished with Q-tips in the paste or with cotton wadding
on the end of a sharpened bamboo skewer. Depending on the design of your object,
it may not be desirable to over-clean every crevice, as this decreases the overall
contrast of the detailing. It is important to remove all residual polish with
distilled water. Drying may be accelerated by adding ethanol to the rinse water,
or by giving the object a final wipe with ethanol.
POLISHING METHOD 2
Some statues may not respond to the special treatment outlined above because
the oxidation layers are too thick. For an admittedly more abrasive method,
use "Solvol Autosol" for general purpose polishing. Test for the degree
of polish you wish to achieve on a small inconspicuous part of the object. Buff
on the polish with a clean rag. The surface must be rinsed with mineral spirits
after polishing to remove any polish residues. This polish can be recommended
because it contains less ammonia than other commercial brands. Ammonia can cause
long term damage to valuable bronze objects.

Polishing exposes fresh, reactive metal to the atmosphere and, therefore, to
further oxidation. You may wish to coat objects that will not be used. We lacquer
valuable silver and brass for their protection. This also eliminates the need
for frequent polishing - a process that inevitably wears away the metal surface
if done frequently.
Wax
For most collectible bronze and brass statues, the best coating we can generally
recommend is wax. Wax provides a relatively flexible coating that is easily
applied and that can be renewed. It can be used on top of original patinas and
lacquers that you do not wish to disturb, as long as they are cleaned first.
Use "Renaissance" wax, or other "microcrystalline" waxes
in most cases, because it is inert and will not yellow over time. It is applied
to a degreased surface with a clean cloth, and buffed out with a rag or bristle
brushes (shoe polish brushes are great for this purpose).
For better adhesion, you may wish to dilute the wax in mineral spirits or varsol,
brush it on, let the solvent evaporate and then buff with a rag or soft shoe
polishing brush. An alternative, on objects made entirely of metal, is to gently
and briefly heat the degreased surface with a hair dryer before applying the
wax. (Do not try this if heat sensitive materials such as wood and ivory are
nearby.)
Again, wax is not an appropriate coating for all metal surfaces, especially
where it is impossible to cover the whole object, or where the slightly glossy
finish would be inappropriate.
Lacquers
Lacquering involves the use of solvents to clean the metal properly (acetone
or tri-chloroethane). On large areas of metal a spray-applied lacquer achieves
the most even and durable finish. Spray lacquering is a task best left to qualified
individuals with the training and equipment necessary to do a good job. Poorly
applied lacquers can actually cause more severe corrosion if small areas are
left exposed.
If there are small areas or pieces of a bronze that need coating, you may achieve
satisfactory results by brushing on a lacquer. We recommend "Incralac"
lacquer, which is formulated for use on copper and copper alloys. It is soluble
in the solvents xylene and toluene and must be used in a well-ventilated area.
(Please request a Material Safety Data Sheet and instructions when you order
this product). The metal must first be scrupulously clean, and you should always
wear gloves to handle the artifact after it has been polished. Just prior to
applying the lacquer, the artifact should be given a final degreasing with acetone.
Lacquer gives a shiny luster to the metal.
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