The marquise cut features a distinctive elongated shape with pointed ends, offering the largest face-up area of any diamond shape for its carat weight. Its boat-like silhouette creates a dramatic, regal presence on the finger and makes the stone appear significantly larger than other shapes of the same weight.

A halo setting surrounds the centre diamond with a border of smaller pavé diamonds, creating a frame of light that makes the centre stone appear 20–30% larger. Halo settings add vintage character and maximum sparkle, catching light from every angle.

Under £2,500, a 1ct lab-grown diamond engagement ring in platinum or 18K gold is well within reach — with budget left over for a more intricate setting style such as halo or side stone.