Certified Lab-Grown Marquise Diamonds | LabGems Antwerp
Marquise cut lab-grown diamonds are among the most demanding shapes to evaluate. The elongated boat profile with two pointed ends requires precise symmetry across both axes — any deviation between the two points or between the upper and lower curves is immediately visible. Marquise cuts also exhibit pronounced bow-tie effect characteristic of elongated brilliant cuts, requiring case-by-case visual selection. LabGems holds IGI-certified marquise cuts in active Antwerp inventory with priority on symmetry and minimal bow-tie selection
Sourcing and Specifications
Active Antwerp inventory includes marquise cuts from approximately 0.30ct through 3.00ct, with extended availability for larger statement sizes on request. All certified stock is supplied with IGI documentation. Standard sizes ship within 1 business day; custom specifications ship within 7 business days. A €500 minimum applies across all certified purchases. Real-time inventory is searchable through the certified diamond search platform.
Symmetry Across Two Axes
Marquise symmetry evaluation requires checking both the longitudinal axis (point-to-point alignment) and the transverse axis (upper curve to lower curve symmetry). Misalignment between the two points causes the stone to appear visibly tilted face-up. Asymmetry between the upper and lower curves makes one side of the stone look fuller than the other. Both faults are immediately visible to clients and reduce retail conversion regardless of other specifications. Trade buyers should prioritise Excellent symmetry grading; Very Good is a fallback only when the visual evaluation confirms balanced geometry.
Bow-Tie Evaluation
Bow-tie effect — a dark band running across the centre of the stone — is present in nearly all marquise cuts due to the elongated brilliant facet geometry. It cannot be eliminated entirely, but well-cut stones minimise its visibility. Trade buyers should evaluate marquise inventory through detailed face-up imagery or in-person inspection rather than relying on grading certificates alone, since bow-tie is not a graded specification. Severely visible bow-tie should be avoided for retail presentation; subtle bow-tie is acceptable. The oval and pear cuts share similar bow-tie evaluation requirements.
Vintage Retail Positioning
Marquise cuts originated in 18th-century French jewellery and carry strong vintage and heritage associations. Retail conversion is most reliable when marquise inventory is positioned toward Edwardian, Art Deco, or Belle Époque-inspired collections rather than contemporary engagement defaults. East-west settings, navette designs, and three-stone configurations with tapered baguettes pair effectively with marquise centres. The cut also performs strongly in pendants and statement earrings where the elongated outline creates visual length. For coloured marquise alternatives in vintage settings, see the coloured lab-grown diamonds collection.
Selection Notes for Marquise Cuts
- Excellent symmetry grading prioritised across both longitudinal and transverse axes
- Visual bow-tie evaluation through face-up imagery is essential; certificates do not capture this
- L:W ratio 1.85-2.00 captures the most balanced commercial proportion
- VS2 or better clarity for stones above 1.00ct; SI grades viable in smaller sizes
- Vintage and heritage retail positioning converts more reliably than contemporary
Frequently Asked Questions (FAQs)
Bow-tie is not graded on certificates, so visual evaluation is required. Request face-up imagery under diffuse lighting and check for a dark central band. Severely visible bow-tie should be avoided for retail presentation.
1.85 to 2.00 is the most balanced commercial range. Ratios closer to 1.75 read as shorter and more rounded; ratios approaching 2.25 emphasise extreme elongation.
A €500 combined minimum applies across all certified diamond purchases. Marquise cuts can be combined with other shapes from active inventory to meet this minimum.
Marquise suits vintage and heritage retail positioning more reliably than contemporary engagement. For contemporary elongated inventory, prioritise oval cuts.