Every few months someone asks us the same question across the counter: are lab diamond prices still falling? The honest answer is yes — but the average hides the part that actually affects what you pay.
Wholesale lab-grown prices fell about 13% year over year in the second quarter of 2026, according to Edahn Golan's Lab-Grown Wholesale Price List, the benchmark most of the trade watches. The index now sits roughly 96% below where it started in 2018. If you stop reading there, you'd assume every lab diamond is cheaper than it was last year.
It isn't. The market has split by size.
One carat has stopped falling
One-carat rounds were up 1% year over year in Q2 2026 — the first time this size has firmed since lab-grown became a mainstream category. Demand at one carat is deep and steady, and growers have had years to optimize production at that weight. There's very little air left in the price.
One and a half carats are still drifting
The 1.50–1.99ct range fell about 11%.
Two carats and up fell hard
Two-carat rounds dropped 20% in a single year. Three-carat stones continue to slide as well.
The reason is production, not fashion. A grower running the same reactor for the same number of weeks can push larger rough through it than they could a few years ago. Bigger stones are where the new capacity landed, so bigger stones are where the price pressure landed. Small stones were already cheap and had nowhere to go.
“Here's what we're actually seeing in the store this year: more customers asking to look at natural diamonds again. Some of that is the marketing money the natural side has put back into the category. Some of it is the pricing story above — when a lab stone drops in value that quickly, a certain buyer starts asking what holds its value instead.
And the language is changing too. In September 2026, CIBJO — the World Jewellery Confederation, the body that publishes the industry's Blue Book standards — removed ‘laboratory-grown' and ‘laboratory-created' from its approved terminology. Going forward, its standard word is synthetic. Russia, Belgium and France have made similar moves, and the African Diamond Producers Association is lobbying for the same. Here in the U.S. the FTC still permits ‘lab-grown' and ‘lab-created,' and isn't scheduled to revisit its Jewelry Guides until 2028 — so nothing changes on our tags today. But you'll start hearing the word synthetic more often, and it isn't an insult. It's a description.
None of this means lab is fading. Lab diamonds are still selling strong for us. What's changed is that they aren't a trend anymore — they're a category, with their own buyer and their own reasons. I can sell you either one honestly. I just want you to know which one you're choosing and why.”
The part nobody enjoys hearing
Falling prices cut both ways. A stone that costs less to buy today is also worth less to resell tomorrow. Natural diamonds generally resell in the range of 25–50% of retail. Lab-grown typically resells for 10–30%, often less, and there is no established secondary market to speak of.
We don't think that's a reason to avoid lab-grown. It's a reason to buy it for the right motive. A lab diamond is a way to wear a larger, cleaner stone than the same budget would otherwise buy. It is not an investment, and anyone selling it to you as one is not being straight with you.
One more thing worth knowing
Since GIA stopped issuing 4Cs reports for colorless lab-grown stones, IGI has become the working standard for lab certification. You'll still see people online calling IGI illegitimate; that's out of date. The clean rule is GIA for natural, IGI for lab — and either way, buy the certificate, not the seller's description of it.
What this means if you're shopping right now
If you're buying around one carat, waiting is no longer a strategy. That price is where it's going to be. Timing the market at this size costs you months and saves you nothing.
If you're stretching toward two carats or more, this is the best value the category has ever offered — and it's the size where an old quote will burn you. Any price you were given six months ago on a two-carat lab stone is now high. Ask for a fresh number, from anyone, including us.
Our verdict
At one carat, buy when you're ready — the price has found its floor. At two carats and above, this is genuinely the moment, but insist on a current quote rather than an old one. And whatever the size, choose lab-grown because you want the look and the size, not because you expect to get the money back. If holding value matters more to you than size, that's the conversation where a natural stone earns its keep — and it's a conversation we're having more often this year.
If you'd like a current, no-pressure number on a specific size and shape, come see us at our Williamsville showroom or reach out and we'll price it for you today — with the certificate in front of you.
