Keeping a sterling rakhi from going black

Sterling silver is 92.5% silver and 7.5% copper, and it is the copper that misbehaves. Exposed to air and humidity — and Noida in August has plenty of both — it forms a dark layer on the surface. This is tarnish, not damage, and it comes off.

The single most effective thing you can do is keep the piece in a closed bag when it is not being worn. Airtight beats decorative: a small zip pouch does more good than a velvet box with a gap in the lid.

Skin contact actually helps. Silver worn regularly tarnishes far more slowly than silver in a drawer, because the natural oils keep the surface conditioned. The keepsake left untouched for eleven months is the one that goes black.

To clean it: warm water, a drop of mild dish soap, and a soft toothbrush for the recesses. Dry it completely with a soft cloth. Do not use toothpaste, and do not use the foil-and-baking-soda trick on an oxidised piece — it strips the deliberate darkening out of the recesses and leaves the design looking flat.

Keep it away from perfume, hair products and chlorine. Put the rakhi on last when getting ready, and take it off before a swim.

If a piece has gone properly black after years in storage, any jeweller will re-polish it for very little. It is worth doing rather than replacing.