Mystique

Mystic topaz never settles on one colour. Look once and it's violet. Tilt it and it slides into green, teal and a quick flash of pink, like the inside of a seashell.

Here's the trick: each stone is a natural white topaz with a micro-thin coating that splits light into a rainbow. That's why mystic topaz costs so little for something this showy, and why no photo quite catches it.

Mystique earrings hang a pair of small stones from slim sterling silver drops, so they swing a little when you walk and catch the light every time. They're light, easy to wear all day, and noticeable without being loud.

One pair, a dozen moods. Wear them with black and they become the whole outfit. Wear them with colour and they'll find a shade in it to match.

Care is simple: wipe them with a soft cloth and keep them away from abrasive cleaners, which can wear the coating.

A good gift for someone who's hard to buy for, because nobody already owns this exact colour.