A halo setting rings the centre stone with a circle of smaller diamonds. The effect is twofold. It makes the centre stone read considerably larger than its carat weight, often by half a millimetre or more in apparent diameter, and the surrounding stones catch light from angles the centre stone cannot reach, so the whole ring stays lively even in poor lighting.This collection includes Bella, Carson, Chelsea, Isabella, Milano, Monza, Olivia, Paris, Toulon and Venice. Several pair a coloured centre stone with a white diamond halo, which is where the design earns its keep, since the contrast defines the outline of the centre stone and intensifies its colour.Halo rings are the most efficient way to get visual size from a given budget. A well cut stone in a halo will out present a larger solitaire costing considerably more. The trade off is upkeep. More stones means more settings, and the small pavé stones around the halo should be checked periodically, which is a straightforward job we handle in the workshop.The style also protects the centre stone, since the halo sits slightly proud and takes knocks that would otherwise hit the main stone.Our guide to ring styles compares halo with solitaire and trilogy settings, and setting a budget for an engagement ring explains how the choice affects what your money buys.