Lab-Grown Diamond Engagement Ring

When light catches the elongated silhouette of a marquise diamond, it traces a path of tapered brilliance that feels both bold and intimate. This semi-set three-stone engagement ring in polished platinum frames a 9 x 4.5 mm marquise center, inviting your choice of lab-grown diamond to complete its story.

Each platinum band is hand-forged in our Williamsburg studio, shaped for a comfortable fit that rests low against the finger. The three-stone setting balances architectural elegance with everyday wearability, its secure prongs crafted to protect while allowing maximum light to animate the stones. The finish is meticulously inspected to ensure a smooth, gleaming surface that complements the diamond’s fiery facets.

Our commitment to ethical jewelry shines through the use of lab-grown diamonds, offering clarity and sustainability without compromise. This design suits those who appreciate a statement ring that remains refined—its slim profile pairs effortlessly with stacking bands or stands alone with quiet confidence.

Should you need resizing, our in-house artisans provide precise adjustments to maintain the ring’s integrity and comfort. Typical lead times reflect the care poured into each custom piece.

Explore this semi-set marquise engagement ring in person at our Williamsburg studio or begin your custom design journey online, where expert guidance awaits.

Haejin Jewelry is a Brooklyn-based fine-jewelry studio specializing in lab-grown diamond engagement rings. Our expertise in ethical craftsmanship and custom design reflects the creative spirit of New York City’s artisanal community.

See how your design comes to life with our Ring Design Online, or start a truly custom piece from scratch in our Williamsburg studio.

Explore our Guides & Education and Stories & Lifestyle for diamond education, care tips, and real studio stories.

Finished for daily wear — a low-profile silhouette and polished edges help minimize snagging.