A San Diego jewelry designer says lab-grown diamonds have moved rapidly from an alternative choice to a mainstream option for custom engagement rings, a shift he is witnessing firsthand among couples visiting his La Jolla studio.
Carl Blackburn of C. Blackburn Jewelers said couples increasingly arrive at consultations already considering a lab-grown diamond, and often specifically requesting one. "Just a few years ago, people would come in asking whether they should even consider a lab-grown diamond," Blackburn said. "Now, many couples already know it is an option and want to see what their budget can achieve with one."
The change in La Jolla reflects a broader national trend. According to The Knot's 2026 Real Weddings Study, lab-grown diamonds accounted for 61 percent of engagement ring center stones purchased by couples in 2025 — a majority share that signals how quickly the category has crossed into the mainstream.
For many couples, Blackburn says, the appeal begins with value. Because lab-grown diamonds typically cost substantially less than comparable natural diamonds, buyers may be able to choose a larger center stone, improve color or clarity, or devote more of their budget to the design and craftsmanship of the ring itself. "For some couples, it means choosing the two- or three-carat diamond they really wanted instead of compromising on size," Blackburn said. "For others, it means putting more of their budget into creating a completely custom ring."
Lab-grown diamonds have essentially the same chemical composition and crystal structure as naturally formed diamonds and share the same hardness and optical properties. Their principal difference is origin. Motivations vary: some couples are driven mainly by price, while others prefer a diamond that does not require traditional mining or want greater transparency about how their stone was produced.
The economics also influence expectations around size. The same 2026 study from The Knot found that lab-grown diamond center stones averaged 2.0 carats, compared with 1.6 carats for natural stones. Blackburn says that difference can be especially significant in custom engagement ring design, where the proportions of the center diamond influence the entire look of the ring. "A larger diamond can completely change the architecture of a design," he said. "When clients have more flexibility with the center stone, it gives us more possibilities for the ring surrounding it."
The implications extend beyond one studio or one purchase. A majority lab-grown market could reshape pricing and inventory expectations across the jewelry trade, pressuring retailers to stock and explain both categories while giving budget-conscious buyers access to larger stones than natural-diamond pricing would typically allow. Blackburn continues to design engagement rings featuring natural diamonds for clients who value their rarity, geological history, family significance or traditional appeal. "There are good reasons someone might choose a natural diamond, and there are good reasons someone might choose lab-grown," he said. "What matters is understanding what you are buying and choosing the stone that makes sense for you."
For couples who choose lab-grown, Blackburn says the decision increasingly comes without the hesitation that surrounded the category when the stones first entered the consumer market. "What has changed most is the conversation," he said. "People aren't necessarily asking, 'Is it okay to buy lab-grown?' anymore. They're asking what size, shape and design they can create with it." He added that whether the diamond came from the Earth or a laboratory, it is only one part of the engagement ring: "The meaning comes from the people, their story, and the design we create around it."
C. Blackburn Jewelers is a custom jewelry design studio in La Jolla, California, led by Blackburn, specializing in custom engagement rings, wedding jewelry and one-of-a-kind fine jewelry. More information is available at CarlBlackburn.com.
