Orbital Pendant

A coloured stone set within a ring of mother of pearl, cut as a doughnut so the gem sits inside the aperture with shell all around it rather than metal. Round brilliant diamonds are set into the frame.

Around the edge of that face runs a band set perpendicular to it, carrying a row of stones — and in the medium and large sizes that band revolves. The face holds steady while the colour travels around it, so the pendant keeps moving as the wearer does. The small size is set fast and wears as a fine everyday jewel.

The band changes with the stone. Malachite and garnet are domed, set face up so the curve stands outward and the light rolls slowly across it. Blue topaz and amethyst are faceted, set face down, so it is the pavilion that shows and the light comes back in points. One version turns quietly; the other sparkles as it goes.

Cutting nacre as a ring leaves a very fine inner edge in a material grown in layers, and that edge is where the work shows. The shell shifts through cream, pink and the palest green as the light crosses it, so even the frame carries colour of its own.

In 14-karat gold — white, rose or yellow, chosen for the stone it holds.

Four stones, each in its own size and metal: blue topaz in white gold at 10 by 10 millimetres, cabochon garnet in rose gold at 16 by 16, sugarloaf malachite in yellow gold and amethyst in white gold, both at 22 by 22.

From Orbital Jewels, within Kinetic.