Marquise Cut Lab-Grown Diamonds: Complete Buying Guide 2026
Quick Answer
Why choose a marquise cut lab-grown diamond?
Marquise cuts have the largest face-up surface area of any diamond shape — approximately 15% larger than a round brilliant of the same carat weight. Their dramatic dual-pointed shape creates the most striking elongating effect on the finger of any shape. Bold, distinctive, and historically one of the most regal diamond cuts.
📊 Marquise diamonds have the largest face-up size of any shape — ~15% larger than equivalent round brilliants. Lab marquise diamonds start from ~$350 for 0.5ct. Both pointed ends require V-tip prong protection.
The Largest Face-Up Size of Any Shape
If you want the most visual impact per carat, the marquise delivers more than any other shape. A 1ct marquise measures approximately 10.5mm × 5.5mm — compare that to a round brilliant at 6.5mm diameter. The elongated form simply covers more finger surface area, creating a dramatic visual presence that punches above its carat weight.
For lab diamond buyers on a budget, this is particularly compelling: a 0.75ct marquise lab diamond will look as large or larger than a 1ct round brilliant at a fraction of the price.
The Elongating Effect
The marquise's two pointed ends create the most dramatic elongating effect on the finger of any shape. Worn horizontally across the knuckle, the stone appears to reach toward both sides, creating a visually wider stone. Worn vertically (point toward nail), it creates a slimming, lengthening effect on the finger.
Most marquise diamonds are set horizontally — this is the traditional orientation and maximizes the visual impact of the shape.
Bowtie Effect — Always Check Video
Like oval and pear shapes, marquise diamonds are vulnerable to the bowtie effect — a dark shadow across the center of the stone. Always use James Allen's 360° HD video to inspect any marquise diamond before buying. A faint bowtie is acceptable and normal; a strong bowtie significantly detracts from the stone's beauty.
Optimal depth (58–62%) reduces bowtie severity. Avoid stones with depth over 66%.
Setting Requirements — Protect Both Points
Both pointed tips must be protected with V-tip prongs — this is essential, not optional. The tips are sharp and can chip if struck directly. The center belly section is held by 4–6 side prongs. Never choose a setting without proper V-tip protection on both ends.
Pricing — 1ct Marquise G/VS2 IGI
| Retailer | 1ct Marquise G/VS2 |
|---|---|
| Clean Origin | $820–$1,100 |
| James Allen | $870–$1,200 |
| Brilliant Earth | $1,000–$1,380 |
| Blue Nile | $920–$1,250 |