Lab-Grown Diamond Engagement Ring

Imagine the delicate silhouette of a marquise diamond, its tapered points tracing a subtle arc that elongates the finger with quiet elegance. This semi-set halo engagement ring in platinum frames a 9 x 4.5 mm marquise center stone, ready to be chosen and set with your ideal lab-grown diamond.

Crafted in cool, polished platinum, the mounting balances strength with refined lightness. The halo setting surrounds the center with a gentle circle of smaller stones, enhancing brilliance without overwhelming the sleek profile. Designed for everyday wear, the band sits low and smooth, offering a comfort fit that slips easily beneath gloves or alongside stackable bands.

Each piece reflects a commitment to ethical jewelry: the lab-grown diamond option ensures clarity and sparkle with a smaller environmental footprint. This ring suits those who appreciate architectural grace paired with a romantic whisper, ideal for hands that favor elongated shapes and subtle drama.

Should you wish to adjust the fit, resizing is available to accommodate your lifestyle seamlessly. Lead times vary depending on stone selection, allowing a personalized pace for your custom design journey.

Visit our Williamsburg studio to explore this semi-set halo or begin your custom design online—where Brooklyn craftsmanship meets thoughtful, modern romance.

Haejin Jewelry is a Brooklyn-based fine-jewelry studio specializing in lab-grown diamond engagement rings, blending expert craftsmanship with ethical practices to create pieces that resonate with New York City’s distinctive spirit.

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.