Lab-Grown Marquise Diamonds

The marquise is having a revival, and grown material has not fully caught up with it. Cutters follow demand, and demand has been concentrated in rounds and ovals for years, so the marquise selection here is smaller than in any of the popular shapes — in lab-grown just as in mined. When you find one with the outline you want, it is worth moving on it.

What lab pricing changes is which compromise you avoid. In mined marquise, the long shape means the cutter is working with an awkward piece of rough, and stones that combine good symmetry with a light centre are priced accordingly. Here you can hold out for both.

Judge in this order. Outline first — the two halves should mirror each other and the points should line up across the long axis. Then the bow-tie through the middle: nearly every marquise has one, and the 360° video will tell you in seconds whether it flickers or sits there as a permanent grey band. Only then look at colour, which this shape hides reasonably well.

Set it with V-prongs at both ends. The points are thin, and that is true regardless of how the stone was made.