Halo engagement rings feature a ‘halo’ of smaller diamonds that encircle the centre stone, adding more sparkle and maximising the central stone so it appears larger and more impressive. This is a style that commands attention, in all of its many forms: from a cluster diamond halo to a diamond solitaire with a halo surround. Choose a diamond centrepiece to complement its halo, or a coloured stone, such as ruby, for an eye-catching contrast.