Storing jewellery so it doesn't tarnish

Volcanoes, sewers and rubber bands

The Canadian Conservation Institute keeps a list of things that give off the sulphur gases that tarnish silver. Some are what you would expect: volcanoes and hot springs, sewer gas, coal-fired heating, eggs. Others are closer to home. Rubber bands. Pencil erasers. Rubber and latex gloves. Wool and wool felt. Certain paints, glues and modelling clays. And, the list notes with admirable frankness, people.

You can't do much about the volcanoes. But almost everything on that list that sits near a piece of silver in a drawer can be moved, and that is the heart of storing jewellery well. Tarnish is a reaction between silver and the air around it. Change the air, and you change the tarnish.

What tarnishes silver

Tarnish is mainly silver sulphide, formed when silver reacts with sulphur-containing gases, most commonly hydrogen sulphide. On sterling silver, the copper in the alloy reacts too, which is why sterling tarnishes faster than pure silver.

The Sheffield Assay Office adds a few household culprits to the conservators' list. Paper, cardboard, foams and adhesives can release sulphur, and inside a small closed box it has nowhere to go. Wooden drawers and cabinets can speed up tarnishing. So can foods such as eggs, onions and salad dressings, and elastic and woollen things stored nearby.

Skin matters too. Fingerprints leave salts and oils behind, and the salt can react with silver to leave marks on a polished surface. Conservators handle silver in clean cotton gloves for that reason. For jewellery, wiping a piece with a soft, dry cloth before putting it away does much the same job.

Keep it dry

Humidity is the accelerator. For the same amount of sulphur in the air, silver tarnishes faster as the relative humidity climbs, and conservators advise keeping it below 50%. The Sheffield Assay Office's advice is to keep silver away from damp places such as basements and attics, and to dry pieces straight after washing.

Silica gel is the conservators' standard way of keeping air dry in a closed space, and the Canadian Conservation Institute suggests a small container of it inside a storage bag or display case. It only works while it can still absorb moisture, which is why conservators specify desiccated, that is dried, silica gel. The little sachets that come in shoe boxes and handbags are the same material.

Sealed bags, cloths and strips

The museum method, scaled down to a jewellery box, is simple. The Canadian Conservation Institute's advice for silver in storage is:

• Bag each piece separately in a polyethylene bag and seal it, with tape, by heat or with a self-sealing bag.
• Wrap or support it in acid-free, unbuffered tissue, which is sulphur-free and evens out changes in humidity.
• Add a little silica gel and activated charcoal to the bag. The silica gel keeps the air dry, and the charcoal absorbs tarnishing gases.
• Or wrap it in a tarnish-inhibiting cloth before bagging it.

The National Association of Jewellers gives the same advice in shorter form: keep silver jewellery in separate airtight bags, and avoid humid places.

One warning from the Sheffield Assay Office is worth knowing: don't wrap silver in newspaper, bubble wrap or plastic, which can promote tarnish or trap moisture. A clean, sealed bag around a clean, dry piece is a different thing from silver wrapped damp or in whatever was to hand.

What is in an anti-tarnish cloth?

The best ones are embedded with tiny particles of silver. Any tarnishing gas that reaches the cloth reacts with the silver in the fabric first, before it reaches your jewellery. The Canadian Conservation Institute calls these cloths particularly effective, and notes a quirk of how they are made: they come only in dark brown. Cloths that contain metal salts instead are also sold, but it rates them as less effective.

Don't confuse an anti-tarnish storage cloth with a polishing cloth. A polishing cloth is impregnated with a fine abrasive for removing tarnish. A storage cloth is for wrapping.

Anti-tarnish strips and bags

Anti-tarnish strips and blocks work on the same idea as the charcoal: they sit near the silver and soak up the sulphur gases before the silver can. The Sheffield Assay Office suggests them for storage boxes and displays, along with tarnish-reducing bags and pouches. Makers rarely say exactly what is inside, and like silica gel they don't last for ever, so follow the packet's guidance on when to replace them.

The exceptions: pearls and opals

Everything above is about silver. Some gems want almost the opposite. The Gemological Institute of America notes that pearls and opals draw moisture from the air, so keeping them somewhere very dry can do more harm than good. It also advises against storing pearls in plastic bags for long periods.

Light and heat are the other enemies. Over time, too much light can fade amethyst, kunzite, topaz and shell cameos, and bleach pearls, while amber can darken. A jewellery box on a sunny windowsill looks lovely; with the lid closed and the pieces inside, it is a better place for the jewellery too.

Tangles and scratches

Tarnish is one storage problem. Pieces damaging each other is the other. The Gemological Institute of America is blunt: jewellery should never be tossed into a drawer or onto a dresser, which is "asking for scratches and damaged gems."

• Fasten chains before storing them. The National Association of Jewellers recommends it to stop tangling, and a fastened chain laid straight, or hung from a post, rarely knots.
• Give each piece its own space. Boxes with individually padded slots for rings and posts for necklaces and bracelets are ideal. The pouch or box a piece came in works well too.
• Keep diamonds apart. Diamond is hard enough to scratch other jewellery, including other diamonds, so the National Association of Jewellers suggests storing diamond pieces away from everything else.
• Keep pearls apart too. They are easily scratched by hard gemstones.
• Protect plating. Gold plated and vermeil pieces have only a thin layer of gold, and rubbing against harder pieces wears it. They are best stored on their own.

Travelling with jewellery

The Gemological Institute of America asked one of its exhibit developers, who has packed and shipped jewellery worth millions of dollars, for her tips. Most of them cost almost nothing:

• Carry it with you. Jewellery belongs in your hand luggage, never in a checked bag.
• One piece per bag. Small plastic bags let you see what you have packed, and stop pieces rubbing against each other. Push an earring post or brooch pin through the bag so it can't move.
• Thread chains through drinking straws, fastened, to stop them tangling.
• Try a pill box. The days of the week make a ready-made planner, and the box protects jewellery from whatever else is in your bag.
• Skip the cotton wool. It leaves fibres caught under claws. Plastic bags or cling film are better.
• Pack a soft cloth, such as a polishing or glasses cloth, for a wipe before wearing.
• Photograph what you take, and tell your insurer your travel dates.
• Take less. A few favourite pieces travel better than the whole box.

Pearls are the exception again. The same advice says not to leave them in plastic bags for long, so unpack them into a soft pouch when you arrive.

Back to the list

The conservators' list of sulphur sources runs from volcanoes to rubber bands, and most of it is out of reach. What isn't is the few centimetres around each piece: a sealed bag instead of an open drawer, a sachet of dry silica gel instead of a damp windowsill, a fastened chain instead of a knot. Silver kept that way needs far less cleaning, and much of the work of polishing it simply never has to be done.