Antique silver has a glow that modern polishing rarely matches, and a softness that modern polishing can destroy. The same enthusiasm that gets a teapot looking bright again can flatten bright-cut engraving, thin a silver-plated rim, or wear down the hallmarks that give a piece much of its value. None of that happens overnight. It happens with the fifth polish in ten years.

The reassuring part is that the safest methods are usually the ones that need the least equipment: a bowl, a soft cloth, warm water and a bit of patience.

Tarnish is not dirt, and it is not on the surface

Tarnish is silver sulphide, a chemical change in the top layer of the metal itself. Sulphur compounds in the air, in rubber, in wool, in some papers and in certain foods all start the reaction. A yellow film becomes brown, then near-black.

That matters because you cannot scrub tarnish off the way you scrub a stain off a worktop. Anything abrasive enough to shift silver sulphide is also removing silver. On a solid sterling spoon the loss is measured in microns; over decades it blunts the edges of decoration. On silver plate, where the silver layer may be only a few microns thick to begin with, a few enthusiastic sessions can expose the base metal underneath — a dull grey patch that no amount of polishing will fix.

Mistake one: reaching for the abrasive polish

Abrasive products are everywhere, and a surprising number of them end up on silver. The most common offenders:

• Toothpaste, which contains fine silica-based abrasives and is far too harsh for silver.
• Cream cleaners and scouring powders designed for sinks and hobs.
• Wire wool, scouring pads and metal brushes.
• Impregnated "miracle" cloths and mitts that feel faintly gritty.
• Metal polishes intended for brass and copper.
• Bicarbonate of soda or salt rubbed on as a dry paste.

All of them cut metal, and some remove tarnish quickly precisely because they are removing the layer it sits in.

What to do instead

Use a polish made specifically for silver, and use it sparingly. A small amount on a soft, clean cotton cloth, worked gently with the grain of the surface rather than in hard circles, will lift light tarnish without reshaping the piece. Rinse any residue off afterwards; polish left in crevices dries into a grey paste that is far harder to remove later. If a piece only has a faint bloom of tarnish, warm soapy water and a soft cloth may be all it needs.

Mistake two: dipping first and asking questions later

Liquid silver dips are dramatic. Thirty seconds and the piece looks new. They work by dissolving the tarnish chemically, and that is where the trouble starts.

Dips strip the soft grey oxide that sits in the recesses of engraved and chased decoration — the very thing that gives an antique piece its depth. Results vary, but a piece dipped too often can end up looking flat, slightly yellow or unnaturally white, like a reproduction. Dips also attack other materials. Pearls, opals, turquoise, coral, ivory, enamel, niello and gilding can all be damaged by them.

If you do use a dip on a plain, undecorated piece with no stones, keep the immersion short, follow the maker's instructions, and rinse and dry thoroughly afterwards. Never leave pieces sitting in the solution. If a piece is plated, worn, gilded or set with anything at all, the answer is no.

Mistake three: treating silver like stainless steel

Silver responds badly to a few everyday habits.

• The dishwasher. Detergent, salt, high heat and contact with other metals are all unkind, and damage to plate or to glued and riveted handles can be permanent.
• Soaking. Leaving silver to stand in water, especially alongside cutlery of other metals, encourages corrosion and water spotting.
• Rubber bands. Rubber contains sulphur and will leave a black scar across a bundle of spoons.
• Bare hands on freshly cleaned pieces. Oils and salts leave prints that can etch into the surface over time. Cotton gloves are worth the small expense.
• Newspaper, cardboard and wool as wrapping or drawer lining. They release sulphur compounds.

The gentle method that deals with most pieces

For everyday grime and light tarnish, work through these steps in order and stop as soon as the piece looks right.

1. Clear a padded surface and line a bowl with a soft cloth so nothing knocks against the sides.
2. Half-fill the bowl with lukewarm water and add a couple of drops of mild washing-up liquid.
3. Wipe the piece with cotton wool or a soft cloth, following the shape of the decoration. Use a cotton bud for crevices, hinges and the gaps between fork tines.
4. Rinse in clean lukewarm water. Do not leave it to soak.
5. Dry immediately and thoroughly with a soft, lint-free cloth. Hollow handles should be stood upright to drain, then dried with a hairdryer on its coolest setting.
6. Only if tarnish remains, apply a purpose-made silver polish sparingly, then wash off the residue and dry again.

Speed matters less than sequence. Rinsing and drying are the steps people skip, and they are the ones that leave the streaks.

The foil and bicarbonate bath, and its limits

There is a clever method that removes tarnish without removing silver. Line a glass

Photo: jbom411 / Pixabay