Lab-grown prices do not behave like natural ones. The per-carat line is flat, the fancy-shape discount has inverted, and the retail spread is wider than anything on the natural counter. Every figure below is dated, sourced, and marked with the basis it stands on.
Re-knocked 2026-10-27 by caratdesk: Lepdo wholesale guide 200, 370,358 bytes (newsroom/sources/2026-10-27/desk/lepdo.html), exact-string grep "$350 to $600" 4 hits, dateModified 2026-07-24T11:49:13+00:00 (2 hits). Band unchanged. trade_date stays the date the band was last moved into this file; reread_date is the newest read; source_modified is the page's own modification date. Re-knocked 2026-10-19: Lepdo wholesale guide (https://lepdodiamonds.com/lab-grown-diamond-wholesale-price-guide/) 200, 369,782 bytes (newsroom/sources/2026-10-19/wire/lepdo.html), dateModified still 2026-07-24T11:49:13+00:00, exact-string grep for "$350 to $600" -- 4 hits, band unchanged (the file is 2,483 bytes larger than the 2026-10-12 copy, so the earlier 'byte-identical' wording no longer applies; the range and modification date are what is unchanged). Rings.com (https://rings.com/pages/lab-grown-diamond-price-index) 200, 324,808 bytes (newsroom/sources/2026-10-19/wire/rings.html), still the 18 September 2026 edition (collected 2026-09-17, 251,098 listings, seven retailers), next edition stated as the week of October 26, 2026; grep for "571" -- 15 hits. Neither leg moved, so no figure on this page changed; only the re-knock date advanced. A one-carat round lab-grown diamond asks $545 per carat against $4,581 for its natural counterpart (StoneAlgo shape sample, 25 Jul 2026) — 88.1% less, a multiple of 8.4. The published wholesale band for the same stone runs $350 to $600 for CVD material (Lepdo, re-confirmed byte-identical and unchanged since dateModified 2026-07-24, re-knocked 2026-10-12). The cheapest tracked retail asking price, $281 at Ritani, sits below the middle of that band. The most expensive, $796 at Brilliant Earth, is 2.8 times the cheapest for an identical specification — both figures re-knocked 2026-10-12, still against Rings.com's 18 September 2026 edition (no newer edition published; next due the week of 2026-10-26), which supersedes the 30 August edition entirely (251,098 listings across seven retailers, collected 17 September 2026). That edition also re-published a 1ct Market Median for the first time since June: $571, across the four retailers with continuous 1ct coverage. Re-confirmed 2026-10-12: Lepdo wholesale guide re-knocked, 200, 367,299 bytes (newsroom/sources/2026-10-12/lepdo.html), byte-identical range, dateModified still 2026-07-24, grep for the exact string "$350 to $600" -- 4 hits. Rings.com re-knocked, 200, 324,300 bytes (newsroom/sources/2026-10-12/rings.html), still the 18 September 2026 edition, next due week of 2026-10-26, grep for "571" -- 12 hits. Neither leg moved.
Natural diamonds get more expensive per carat as they get bigger, because big rough is rare. Lab-grown diamonds do not: the per-carat price is flat from half a carat to five, moving between $514 and $631 across the whole ladder. Everything that follows is a consequence of that one line.
| Weight | Lab, stone | Lab / ct | Natural / ct | Multiple | Discount |
|---|---|---|---|---|---|
| 0.50 ct | $293 | $586 | $2,630 | 4.5× | −77.7% |
| 1.00 ct | $581 | $581 | $5,454 | 9.4× | −89.3% |
| 2.00 ct | $1,213 | $606 | $14,216 | 23.5× | −95.7% |
| 3.00 ct | $1,894 | $631 | $23,744 | 37.6× | −97.3% |
| 4.00 ct | $2,315 | $579 | — | — | no natural mark |
| 5.00 ct | $2,568 | $514 | $28,484 | 55.4× | −98.2% |
Across a tenfold range of weight the lab-grown per-carat price moves 23%. Across the same range the natural price moves 983%. The gap between the two is therefore not a constant discount but a widening one: 4.5× at half a carat, 9.4× at one (natural side corrected 2026-09-15, James Allen dropped from the retailer set), 55.4× at five. Buying big is where the saving actually lives.
The 4.00 ct row carries no natural comparison because the natural sample at that weight was too thin to publish and stays blank on the natural list. The lab figure stands alone rather than against a number we would not print.
In natural diamonds every fancy shape is cheaper than a round, because rounds waste the most rough and rough is the cost. In lab-grown there is no rough to waste: the cost is growing time and cutting loss on a crystal that can be grown to order. At one carat the ranking flips. A lab princess asks 23.5% more than a lab round; a natural princess asks 39.4% less. That is a 62.9-point swing on the same two shapes.
| Shape | 1.00 ct | 2.00 ct | 3.00 ct |
|---|---|---|---|
| Oval | +11.2% | +11.3% | +11.9% |
| Pear | −3.9% | −3.3% | +9.1% |
| Emerald | +21.5% | +1.8% | −13.3% |
| Princess | +23.5% | −7.4% | −9.0% |
| Cushion | +14.3% | −8.1% | −19.3% |
| Heart | −2.4% | +0.1% | −7.6% |
| Marquise | — | +29.6% | −15.5% |
| Asscher | — | −0.8% | +5.1% |
| Radiant | — | +4.5% | −10.3% |
The inversion is a one-carat phenomenon, and we will not pretend otherwise. At two carats princess and cushion fall back below round; at three carats six of nine shapes do. Only oval carries a premium at all three weights we track. Anyone quoting a single lab-grown shape premium across all sizes is quoting something that does not exist.
Three consumer guides published this year state the opposite of the live data. Liori (27 March) puts emerald cuts at “30–35% savings compared to rounds” and ovals at 20–25% less. Beyond Carat (15 June) prints oval 15–25% less, cushion 20–30% less, emerald 20–30% less, princess 10–20% less. The live one-carat sample has emerald 21.5% above round, cushion 14.3% above, princess 23.5% above. The guidance is the natural-market ordering, copied across to a market that does not work that way.
No source we track publishes a dollar-denominated colour or clarity ladder for lab-grown diamonds from live inventory. We are not going to model one. On the natural list those two ladders are the backbone of the page; here the honest answer is that the market has not produced them, and a modelled ladder printed next to observed figures would be indistinguishable from data.
| Measure | Figure | Basis |
|---|---|---|
| PriceScope lab matrix, 0.30–0.39 ct, D / IF | $1,227 / ct | Published |
| PriceScope lab matrix, 0.30–0.39 ct, D / VVS2 | $759 / ct | Published |
| Implied IF premium over VVS2 at that weight | +61.7% | Derived |
| PriceScope lab matrix, 0.40–0.49 ct, D / IF | $1,259 / ct | Published |
| Most-bought colour at 1.00 ct, lab | D | Observed |
| Most-bought clarity at 1.00 ct, lab | VVS1 | Observed |
| Most-bought grades at 1.00 ct, natural | G / VS | Observed |
The modal lab-grown buyer takes D colour and VVS1 clarity. The modal natural buyer takes G and VS. Nobody trades down in a market where the top grade costs almost nothing extra — which is the clearest thing anyone has published about the lab colour and clarity ladder, even though it is not a price.
HPHT material carries a premium over CVD at every band published — between 14.5% and 24.0% on band midpoints. The premium is a production fact, not a quality claim: HPHT rigs cost more to run per carat and the two methods yield different colour distributions before treatment. This is the one price structure in lab-grown that has no analogue on the natural counter at all.
| Band | CVD / ct | HPHT / ct | HPHT |
|---|---|---|---|
| 0.50 ct · F–G · VS1–VS2 | $90–160 | $110–200 | +24.0% |
| 1.00 ct · D–F · VS1–VS2 | $350–600 | $400–750 | +21.1% |
| 1.50 ct · F–G · VS1–SI1 | $280–480 | $320–550 | +14.5% |
| 2.00 ct · G–H · VS2–SI1 | $220–420 | $260–500 | +18.8% |
| 3.00 ct · G–H · VS2–SI1 | $180–350 | $210–400 | +15.1% |
Melee under 0.30 ct trades at $50–180 per carat with no method split published.
Same stone, same paper, four counters. At one carat the most expensive asking price is 2.83 times the cheapest, down from 3.84 in the August edition — Ritani raised its 1ct median 26% this edition ($223 to $281), reversing an August decline, while Brilliant Earth's 1ct median eased 7%. At two carats the spread widened to 4.72 times. On the natural counter the equivalent one-carat spread is 2.19 times (five counters, after the 2026-09-15 James Allen correction). Rings.com also re-published a 1ct Market Median this edition ($571, across Ritani/Grown Brilliance/With Clarity/Brilliant Earth) for the first time since June — the 1.5ct and 2ct medians remain withheld under the source's own publication rule (a cell's median only prints when every contributing retailer also had a published figure the prior edition). Clean Origin returned to the panel with n=20 (still below the 30-listing minimum at 1ct; it prints at 1.5ct/2ct, $263/$279 per carat, which this table's four-counter schema does not carry). Re-knocked 2026-10-05: same edition, last_updated still 2026-09-18, all figures (251,098; 571; 281; 796; 2.83) confirmed present by raw-byte grep, none changed.
The cheapest tracked asking price at one carat, $281, sits below the midpoint of the published CVD wholesale band for the same specification ($350–600). Either the wholesale guide is stale, or that counter is selling at or below trade. We print both figures and let the gap stand.
Ninety-six per cent off since July 2018, and the fall is decelerating rather than stopping. The single riser in the entire Q2 list is the one-carat round — the most-traded item in the category, up 1% against an index down 13%.
| Measure | Change | Period |
|---|---|---|
| LGD Wholesale Price Index, year on year | −13% | Q2 2026 |
| Since tracking began, July 2018 | −96% | Q2 2026 |
| Since 2020 | −74% | Jun 2026 |
| Q1 2026, quarter on quarter | −14% | Q1 2026 |
| 1.00 ct rounds, year on year | +1% | the only riser |
| 1.50–1.99 ct, year on year | −11% | Q2 2026 |
| 2.00 ct, year on year | −20% | Q2 2026 |
| Fancy shapes — heart, marquise, oval, pear | −17% | average |
| Square shapes | −21% | some VVS below −25% |
Rough is moving the other way. Chinese producers raised prices at least 30% in recent weeks and Diamond Foundry by about 25%. Polished has not followed yet. If it does, the one-carat round will not be the only riser for long.
| Measure | 2019 | 2025 | Carat Capital, July 2026 |
|---|---|---|---|
| Lab discount to natural, per carat | 26.6% | 72.8% | 88.1% |
| Lab share of engagement rings | 6.3% | 47.7% | — |
| Average lab centre stone | 1.31 ct | 2.45 ct | — |
| 1.00 ct lab, typical | — | $1,000 or less | $545 |
| 1.00 ct natural, typical | — | $4,200 | $4,581 |
The discount has not widened because natural got dearer. Natural is roughly where it was. Lab fell out from under it — and buyers spent the difference on size, taking the average lab centre stone from 1.31 ct to 2.45 ct, up 87.0% in six years. The flat per-carat line makes that trade almost free.
| Measure | Figure |
|---|---|
| Trade buyback, lab-grown | $0 |
| Secondary platforms — eBay, consignment | 20–30% of price paid |
| Natural, typical retention | ~50% |
| Pawn, lab-grown | metal weight only |
A jeweller will not buy a lab-grown diamond back at any price, because they can order a new one at wholesale tomorrow. The absolute loss is still smaller than on a natural stone — losing all of $2,000 beats losing half of $20,000 — but the retention rate is the one number in this category that has not fallen, because it started at zero.
Labrilliante publishes 30–40% retention for lab-grown. It contradicts every trade buyback account we could source and we have not used it.
China produces roughly half the world's synthetic diamond output and about 80% of the Chinese total comes out of Henan province, predominantly by HPHT. India is the largest CVD producer at close to a quarter of global output. The newest comparable production breakdown we could source dates to December 2023 and we flag it as such.
Chinese producers raised rough prices by at least 30% in recent weeks; Diamond Foundry by about 25%. Polished has not followed. Every previous turn in this market started at the reactor, not the counter.
The trade reads the fall as capacity scaling rather than weakening demand — the compression is happening at the producer and migrating down the chain. Lab-grown still took 47.7% of the engagement-ring market in 2024.
Up 1% year on year against an index down 13%. It is the most liquid item in the category and the only line in the Q2 wholesale list that rose.
The average lab centre stone went from 1.31 ct in 2019 to 2.45 ct in 2025, up 87.0%. A flat per-carat curve means going bigger costs almost nothing, so buyers go bigger.
Rapaport publishes no lab-grown price list. On the natural page we declined to reconstruct a copyrighted matrix; here there is no matrix to reconstruct, and no benchmark holding the retail range together either.
Retail asking prices come from live inventory indices. Wholesale comes from a published trade guide quoting bands. They are printed as separate figures and never averaged into a single number.
We show wholesale as the band the source published. Midpoints appear only where we compare CVD against HPHT, because that comparison is internal to one table and one source.
Colour and clarity stay unpriced. A modelled ladder set beside observed figures reads as data, and we would rather print the gap.
The dispersion table holds colour, clarity, shape, cut and lab constant across every retailer, so the range is a pricing difference and not a specification difference.
| StoneAlgo lab-grown price index, all shapes | 25 Jul 2026 | stonealgo.com |
| StoneAlgo 1 ct lab index, n=417,607 | 25 Jul 2026 | stonealgo.com |
| StoneAlgo 2 ct lab index, n=453,915 | 25 Jul 2026 | stonealgo.com |
| StoneAlgo 3 ct lab index, n=317,509 | 25 Jul 2026 | stonealgo.com |
| Rings.com lab-grown price index, n=251,098 | 18 Sep 2026 (fresh edition, collected 17 Sep 2026, re-knocked 2026-10-19, unchanged) | rings.com |
| Lepdo wholesale price guide | 24 Jul 2026 (re-knocked 2026-10-19, range and dateModified unchanged) | lepdodiamonds.com |
| Edahn Golan, Q2 2026 LGD Wholesale Price List | 7 Jul 2026 | edahngolan.com |
| InStore, Q2 2026 LGD wholesale report | 8 Jul 2026 | instoremag.com |
| AIDI, lab-grown wholesale and margin migration | 8 Jun 2026 | aidi.org |
| PriceScope lab diamond price chart, n>400,000 | Jul 2026 | pricescope.com |
| TheCaratCut, lab-grown resale value | 12 Feb 2026 | thecaratcut.com |
| BriteCo lab-grown vs natural report | data to 31 May 2025 | brite.co |
| Rough&Polished, China and India LGD production | 4 Dec 2023 | rough-polished.expert |
| Carat Capital natural diamond price list | 30 Jul 2026 trade/shape data; retail_ct corrected 2026-09-15 (James Allen dropped) | caratcapital.org |
