Lab-Grown Diamond Engagement Ring

Light catches the elongated silhouette of a marquise diamond, its tapered points drawing the eye along the finger with quiet drama. This semi-set three-stone engagement ring foundation in platinum awaits your choice of center stone, designed to showcase the distinctive 6 x 3.5 mm marquise shape—an elegant balance of vintage allure and modern geometry.

Handcrafted in our Williamsburg studio, the platinum band is meticulously finished to a soft matte sheen, offering a subtle contrast to the diamond’s sharp facets. The three-stone setting is engineered for low profile wear, ensuring comfort beneath gloves or daily tasks, while the secure prongs cradle side stones that frame the center with refined symmetry.

Each lab-grown diamond option reflects our commitment to ethical jewelry, combining clarity and sustainability without compromise. The cool platinum’s natural hypoallergenic properties complement the stone’s brilliance, creating a piece designed for everyday grace.

Ideal for those who appreciate architectural lines and a ring that layers effortlessly with wedding bands or stackable styles. The semi-set format invites personal expression, allowing you to select a center stone that resonates with your story.

Resizing is available to ensure a precise fit, crafted with the same care as the original design. Typical lead times reflect our artisanal process, with every ring inspected for structural integrity before it leaves the studio.

Explore this semi-set marquise engagement ring in person at our Williamsburg workshop or begin your custom design journey online—where expert guidance meets thoughtful craftsmanship.

Haejin Jewelry stands as a Brooklyn fine-jewelry studio specializing in lab-grown diamond engagement rings, blending expert craftsmanship with ethical sourcing and a deep connection to New York City’s artisanal heritage.

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

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