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The following copyrighted silver care information has been provided by Jeffrey Herman, Herman Silver
Restoration & Conservation. None of the below guide can be reproduced without written permission from
Jeffrey Herman, PO Box 72839, Providence,
RI 02970, 401/461-6840, jeffherman@silversmithing.com
Cleaning & Caring for Silver Jewellery
Sterling silver is easy to care for. If you follow a few simple steps including proper storage,
keeping your sterling silver tarnish free and sparkling will only
require a small amount of time and effort.
Though this advice is regarding your sterling silver jewellery, it applies to all sterling silver.
All the products mentioned here are products that our silversmith's use and recommend for cleaning sterling silver jewellery.
They are available through most reputable jewellers, and directly through Parap Creations.
Cleaning your sterling silver jewellery
Clean your sterling silver jewellery with a soft 100% cotton (nub free) cloth or flannel cloth
and gently rub off any excess makeup.
Remember silver is a very soft metal, to avoid scratches don't rub it too briskly.
Never use anything but a clean 100% cotton or a special sterling silver cleaning cloth or very soft bristle brush,
like a babies tooth brush or a horsehair silver brush.
For light cleanings use a small amount
of mild liquid detergent to a 1/2 cup of warm water and rinse thoroughly with clean fresh water.
Dry completely before polishing with a soft cotton cloth.
Do not use polishing cloths on gemstones!
Alternatively, use a soft bristle brush and a little mild soap like Dove.
Clean well and then spray with a spray polish.
Let it dry for a couple of minutes then rub off with a soft cloth.
If there are soft porous gemstones in the
jewelry, be careful to keep the spray off the gemstones. We would recommend spraying
the cleaner directly on the cloth and rubbing the area around the gemstone with the
cloth and cleanser. Polish it to a shine with the soft
brush or cloth.
Solid gold is generally cared for in the same way as silver. Articles that are silver plated or gold plated must be cleaned with the same care as solid metals.
As most people would prefer not to spend hours cleaning one item, the methods employed by the likes of museum conservators who generally
clean silver and gold in their collections using calcium carbonate/alcohol mixture will not be discussed.
Sulphur-containing compounds tarnish silver. The most common things to cause tarnish are food (eggs, onions, mayonnaise, fruit juices,
tomatoes, vinegar, ketchup, salt, salty foods, butter, mustard, and tomato sauces), fossil fuels, rubber bands, latex gloves, some plastics and
paints, and wool. Tarnish is accelerated when the silver is exposed to high humidity. Oily deposits from fingers contain relatively high levels
of salt and, if not removed will show up as etched fingerprints which if deep may have to be professionally removed.
If there is no tarnish present on your silver, use a phosphate-free detergent to clean it after use. Silver that is used, then gently washed and
dried immediately will seldom require tarnish removal. When hand- washing, do not allow your silver to come in contact with a metal sink as
silver is soft and will be marked.
Tarnish is easily removed when first noticed (usually a golden hue), but will become increasingly difficult to deal with, as it turns to light brown
and eventually black. Frequent light cleanings, are preferred to waiting until the tarnish gets so stubborn that more abrasive polishes would
have to be employed to remove them.
It may be seen that after cleaning the silver surface has a a purplish stain. The “stain” is oxidized copper and is called firestain.
It can be found on older silver items. It is not generally seen on pieces that have been produced by the large silver companies after the 1800s.
A depletion process can be used to leave the object with a thin pure silver surface that is more resistant to tarnishing.
The stain develops in sterling when oxygen penetrates the outer surface of the object during brazing/ soldering, oxidizing the copper content.
This chemical reaction can extend deep within the silver metal. The oxidised copper can be removed from the surface by the application of an acid.
This leaves a thin fine silver surface, which, if removed by years of polishing, can reveal the copper oxide (firestain) below.
Do not mistake this stain for tarnish! Attempting to remove it will only damage your prized piece.
Chemical dips
Chemical dips work by dissolving the tarnish on an object at an accelerated rate. Silver restorers use dips when heavy,
black tarnish cannot be removed with liquid or paste polishes. Chemical dips are wiped over the object with a cellulose sponge or
cotton ball to avoid over cleaning, for submerging the entire piece for long periods will cause pitting of the object's surface and remove factory-applied patinas.
This surface will act like a sponge and more readily absorb tarnish-producing gases and moisture. The object may then require professional
polishing to restore the original finish.
These dips are made up of an acid and a complexing agent. Acids are corrosive and will damage niello, bronze, stainless steel knife blades,
and organic materials such as wood and ivory. The ingredients can be harmful to the user, which is why silver restorers work in a well-ventilated
area and wear nitrile gloves. Chemical dips should never be used on objects that have sealed components, such as candlesticks and trophies with
hollow feet or teapots with hollow handles. Once the dip leaks into the cavity through small holes or imperfections in the joints, it becomes virtually
impossible to wash the chemical out. For these reasons, a qualified restorer should only use this cleaning technique.
Electrochemical (Galvanic) reduction
This process uses an aluminium or aluminium alloy plate and warm solution of sodium carbonate (washing soda). When the object comes in contact
with the plate in the solution, it removes only light tarnish, not the thick, black tarnish produced by years of neglect.
Pitting of the object can occur if the aluminium plate is not periodically cleaned. Another not-so-obvious problem is scratching of the object when in
contact with the plate.
Objects cleaned by this method may tarnish more quickly than silver that has been polished, for the object's surface will act like a sponge and more
readily absorb tarnish-producing gases and moisture. The solution can also seep into hollow areas such as coffee pot handles,
unsoldered spun beads around the tops of lightweight hollowware, weighted pieces with minute holes, and any porous attachments.
For these reasons, this cleaning technique is not recommended.
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