Lab-Grown Diamonds Market

A one-carat lab-grown round cost a US jeweller USD 191 a carat in the second quarter of 2025, and Indian export data now price an average lab-grown carat near USD 60 against about USD 760 for a natural one. The lab-grown diamonds market covers polished gem diamonds and single-crystal plates grown by high pressure high temperature (HPHT) presses or chemical vapour deposition (CVD) reactors, valued at first wholesale. Douglas Insights sizes it at USD 1.75 billion in 2025, rising to USD 2.29 billion by 2035, a revenue CAGR of 2.74%: 23.62 million carats × USD 74.1 a carat = USD 1.75 billion. Carats grow 8.6% a year while the average carat price falls 5.4%. The clearest signal of that squeeze came on 8 May 2025, when De Beers Group announced it would close Lightbox, noting that lab-grown jewellery prices had fallen 90% at wholesale since the brand launched at USD 800 a carat. The report belongs to our luxury goods and leisure research, and every step of the carat build is set out in the Douglas Insights research methodology.

How much does a lab-grown carat cost against a mined carat in 2025?

USD 74.1 a carat is the 2025 average first-wholesale price across all lab-grown diamonds, against about USD 760 for natural polished carats in India’s export books. The gap reflects factory supply against geological scarcity, and it widens every quarter as reactor and press capacity keeps outrunning jewellery buyers.

Indian Gem and Jewellery Export Promotion Council (GJEPC) data for April 2026 put the average exported lab-grown carat near USD 60, roughly one-thirteenth of the natural figure. Lab-grown stones made up just over half of India’s exported carats but under 10% of export revenue. A US retailer’s acquisition cost for a one-carat round graded by the International Gemological Institute (IGI) fell from USD 207 a carat in the first quarter of 2025 to USD 191 in the second, and that cost was still about twice the Mumbai wholesale trading price.

Where the lab-grown margin sits

Retail tells another story. The top-selling lab-grown item at US retailers in the second quarter of 2025 was a 2.23-carat round at an average USD 917 a carat, carrying a 74% gross margin, up almost 8 points in a year. Wholesale lab-grown prices fell 8.9% in the first quarter of 2025 and 6.7% in the second, and one- to three-carat rounds traded 42% below the same quarter of 2024.

Douglas Insights puts the 2035 average lab-grown carat at USD 42.5, after ten years of 5.4% annual declines. The decline slows from today’s double-digit pace because the cheapest HPHT melee is already near its cash cost, and branded CVD stones above 3 carats hold price better.

Which stones and crystals fall inside the lab-grown diamonds boundary?

Four lab-grown diamond categories sit inside the USD 1.75 billion total: bridal centre stones, fashion jewellery and melee stones, fancy-colour and fancy-shape stones, and technical and optical single crystals. Value is counted once, at the first sale of a polished stone or finished crystal plate, before any jewellery setting or retail markup.

Size bands run from melee under 0.2 carat, through 0.2 to 0.99 carat and 1 to 3 carats, to stones above 3 carats. Both growth methods are tracked separately: HPHT, which dominates small Chinese output, and CVD, which dominates Indian and US production. Buyers are split by channel into independent jewellers, jewellery chains, online retailers and industrial buyers. Natural diamonds, simulants such as moissanite, and diamond grit and powder for abrasives sit outside the lab-grown boundary. For a neighbouring factory-grown crystal used in watch faces and LED substrates, see the Synthetic Sapphire Market report.

Which companies hold the lab-grown diamond supply chain, and on what?

Douglas Insights estimates that three grower clusters, Gujarat CVD, Henan HPHT and US CVD, hold a 91.2% share of 2025 lab-grown gem carats. No single company dominates: positions rest on cheap power, reactor count, cutting capacity in Surat, or a retail brand that can hold margin while carat prices fall.

The miners have retreated. On 8 May 2025 De Beers Group said it intended to close Lightbox, the lab-grown jewellery brand it launched in 2018, and that Element Six would grow CVD diamond only for industrial uses, centralised at its Oregon facility. Chief executive Al Cook said he expected both the cost and the price of lab-grown jewellery stones to fall further. WD Lab Grown Diamonds, a Maryland CVD grower founded in 2008 on Carnegie Institution technology, filed for Chapter 7 liquidation in October 2023 after revenue fell from USD 33 million in 2022.

Lab-grown diamond growers, brands and retailers named in the model

Diamond Foundry’s Spanish plant, backed by about USD 850 million and a 120-megawatt solar park, is described by the Spanish investment agency ICEX-Invest in Spain as able to reach 10 million carats a year at full capacity. Henan Huanghe Whirlwind reported first-half 2023 revenue of about 1 billion yuan, down 21.09%, as HPHT prices slid. Signet’s fiscal 2025 annual report calls lab-grown diamonds a meaningful portion of its sales and inventory, with bridal at 49% and fashion at 45% of merchandise sales.

Why are lab-grown diamond carats still growing 8.6% a year?

Carats sold rise 8.6% a year to 53.9 million by 2035 because lab-grown stones keep replacing mined ones in bridal and fashion jewellery. Douglas Insights splits the volume leg into four contributions: bridal switching 3.1 points, fashion and melee substitution 2.6 points, Asian home demand 1.8 points and technical crystals 1.1 points.

Bridal switching is the largest lab-grown driver, worth 3.1 points. The Knot’s survey of more than 10,000 couples married in 2025 found 61% of engagement rings carried a lab-grown centre stone, up from just over 50% in 2024. Average carat weight rose from 1.7 to 1.9 while average ring spend fell from USD 5,200 to USD 4,600. Each switch adds carats even as the dollar bill shrinks, which is exactly the shape of the base case. Bigger stones, smaller bills. A couple choosing a 1.9-carat lab-grown stone over a 1-carat mined one roughly doubles the carats the trade must grow and cut.

Fashion and melee substitution adds 2.6 points. Pandora dropped mined diamonds in 2021, and Signet’s own filing calls lab-grown stones a meaningful portion of its sales and inventory. Once De Beers announced the Lightbox closure on 8 May 2025, the largest miner-owned lab-grown fashion brand left the field, handing that shelf space to growers and retailers. GemGuide’s April 2025 review of US retail data showed 2024 lab-grown unit sales up 18.6% even as revenue fell 7.2%.

Asian home demand contributes 1.8 points. India’s government backed the domestic chain on 23 February 2023 with a five-year research grant of Rs 242.96 crore to the Indian Institute of Technology (IIT) Madras for lab-grown diamond machinery, seeds and recipes. The same release showed India’s cut and polished lab-grown exports climbing from USD 237.89 million in 2017-18 to USD 1.35 billion in 2021-22. Indian and Chinese consumers now buy stones grown a few hundred kilometres away, at prices local jewellers can quote per gram of gold rather than per carat of diamond.

Technical crystals add 1.1 points. Small base, steady buyers. Single-crystal CVD plates go into heat spreaders for radio-frequency chips, laser windows and quantum sensors, where the buyer pays for thermal conductivity rather than colour grade. Douglas Insights expects the technical segment to grow from USD 217.0 million in 2025 to USD 378.1 million in 2035, the one lab-grown category where prices hold.

What headwinds weigh on lab-grown diamond value per carat?

Price deflation removes 5.4 points a year from lab-grown diamond value, enough to cut an 8.6% carat leg to a 2.74% revenue CAGR. Three restraints explain that drag: excess HPHT and CVD capacity, weak resale value, and disclosure friction between lab-grown and natural stones.

Excess capacity takes 3.6 points. China’s gem-quality output reached about 20 million carats in 2022, which its gems and jewellery trade association put at roughly 40% to 50% of global gem capacity. One Henan county, Zhecheng, makes about 4 million gem carats a year, and a one-carat D/E-colour lab-grown round fell from about 10,000 yuan to about 2,000 yuan within a year.

Resale and gifting doubt takes 1.1 points. Resale is thin. Lab-grown stones have almost no secondary market, so some buyers treat them as fashion rather than heirloom purchases, which caps how far bridal centre stones can climb in carat weight.

Disclosure friction takes 0.7 points. Mixed parcels of natural and lab-grown melee force cutters, graders and retailers to pay for screening on every lab-grown lot. The cost falls hardest on small stones under 0.2 carat, where screening can exceed the stone’s own wholesale value.

Which lab-grown diamond category makes the money in 2025?

Bridal centre stones lead lab-grown diamond value with 44.3%, or USD 775.3 million in 2025, because a single 1- to 3-carat stone carries more value than hundreds of melee pieces. Technical and optical single crystals grow fastest, at 5.71% a year.

Bridal centre stones grow only 1.41% a year because the fastest price falls hit the 1- to 3-carat CVD stones that dominate engagement rings. Fashion jewellery and melee stones, worth USD 605.6 million, grow 3.09% as lab-grown studs and tennis bracelets replace mined melee in chains and online stores. Technical and optical single crystals, at USD 217.0 million, are the fastest-growing lab-grown segment at 5.71%, because semiconductor and optics buyers pay for purity, so their prices barely move. Fancy-colour and fancy-shape stones hold USD 152.3 million and grow 2.68%, helped by pinks and blues that are far cheaper grown than mined.

Where do lab-grown diamonds sell, from New York to Mumbai?

North America buys USD 959.1 million of lab-grown diamonds in 2025, or 54.8% of value, because US bridal buyers switched first and furthest. Asia Pacific grows fastest at 4.97% a year, from USD 383.3 million to USD 622.6 million by 2035.

North America’s share slips as prices fall faster than US carat volumes rise, so it grows just 1.64% a year to USD 1.13 billion. Asia Pacific, at USD 383.3 million, gains because Indian and Chinese buyers now see lab-grown stones made close to home, and India’s domestic jewellery chains price them per carat against gold. Europe holds USD 238.0 million and grows 2.86%, led by the UK, where Pandora first launched its lab-grown range in 2021. The Middle East and Africa, at USD 91.0 million and 3.71% a year, is the wildcard: Gulf jewellery retail is large, but our model treats lab-grown adoption there as early and volatile. Latin America holds USD 78.8 million and grows 1.87%, because our model assumes slow adoption through a thin specialist jeweller network. Country splits come with country tables in the Excel model.

Has the engagement ring switched to lab-grown centre stones for good?

61% of 2025 engagement rings in The Knot’s survey carried a lab-grown centre stone, so the switch is now the US norm. Douglas Insights expects the lab-grown share of US bridal carats to keep rising, but more slowly, because the remaining buyers value mined origin.

Couples now buy size. Average stone size rose to 1.9 carats while total ring spend fell 11.5% to USD 4,600, so the jeweller sells more carat for less money. Brands answered by selling lab-grown stones on size and design, a pattern familiar from other accessible luxury categories such as the Luggage Market, where material cost fell and brand premiums moved to design. Retailers also rebuilt margins: the 74% gross margin on top-selling lab-grown stones shows that falling wholesale prices are not yet reaching the shopper in full.

How fast is HPHT and CVD reactor capacity expanding for lab-grown diamonds?

Capacity for lab-grown diamonds expands faster than jewellery buyers absorb it, with China’s 20 million gem carats in 2022 equal to only 40% to 50% of world gem capacity. Indian CVD reactor counts in Gujarat keep rising, and Diamond Foundry’s Spanish plant targets 10 million carats a year.

HPHT presses in Henan produce most of the world’s small lab-grown stones; Henan makes about 80% of China’s output, and China’s superhard materials association puts the country at about 95% of world lab-grown diamond output. CVD growth has moved to India, where reactors sit beside Surat’s cutting benches, and to the US and Spain, where cheap hydro and solar electricity cut the power bill that dominates CVD cost. Douglas Insights counts 18.84 million lab-grown carats in India’s exports for the year to March 2026, more than the 16.00 million natural carats exported over the same period.

How do GIA’s new grading rules and disclosure standards change lab-grown diamond reports?

From 1 October 2025 the Gemological Institute of America (GIA) stopped grading lab-grown diamonds on its natural 4Cs scales and rates each stone Premium or Standard instead. The change narrows grading to two bands and sets the fee at USD 15 a carat.

GIA announced the change on 26 August 2025, saying it would no longer use the nomenclature created for natural diamonds on lab-grown stones. A Premium lab-grown stone needs D colour, VVS clarity or better and excellent polish and symmetry; Standard covers E to J colour and VS clarity. Stones below that floor get no GIA assessment, and the minimum size is 0.15 carat. Every graded stone carries a “Laboratory-Grown” girdle inscription, which supports disclosure at retail. For buyers, the rule removes the fine colour and clarity steps that once justified price gaps between lab-grown stones, adding to price compression on stones of 1 to 3 carats.

What if lab-grown diamond prices stop falling before 2035?

A faster lab-grown case, with carats up 10.1% and prices down only 3.9% a year, lifts 2035 value to USD 3.08 billion. The base case reaches USD 2.29 billion, and a slower case with 6.4% carats and 7.2% price declines ends at USD 1.54 billion.

The faster case needs capacity to close, as Lightbox did after the 8 May 2025 De Beers announcement, so that growers stop selling below cost. The slower case assumes Henan and Gujarat keep adding presses and reactors and wholesale prices keep falling at the 2025 pace of 6.7% to 8.9% a quarter for longer. A single extra point of carat growth a year adds about USD 220 million to the 2035 lab-grown value. Published forecasts run from about 7.8% to 13.4% a year, well above our 2.74%, because most of them count retail jewellery value rather than first-wholesale stones.

Douglas Exclusive: the carat-price atlas

The carat-price atlas is a Douglas Insights model of lab-grown diamond wholesale prices by grower process and region, built from 191 inputs: 164 price observations and 27 trade and company disclosures. It places every 2025 lab-grown carat in one of six process, region and size cells.

The atlas finds a 6.6-fold spread between the cheapest and dearest gem cells. Size matters more than process. Its Gujarat 1 to 3 carat cell, at USD 96, sits almost exactly at half the USD 191 retail acquisition cost, matching the trade’s own two-to-one rule. Branded US and Spanish CVD stones keep a 65% premium over Gujarat stones of similar size.

Which inputs and cross-checks sit behind the lab-grown diamond carat methodology?

The lab-grown diamond model counts 23.62 million carats across 34 countries and 412 data points, priced at USD 74.1 a carat for USD 1.75 billion. Each carat is traced from grower to first wholesale sale, then priced from atlas cells.

Carats: 18.30 million from India’s polished exports, 1.08 million from India’s home market, 2.87 million polished and sold inside China and Hong Kong, 0.95 million from US, European and other growers, and 0.42 million carat-equivalents of technical crystals. Prices: 23.20 million gem carats at USD 66.1 make USD 1.53 billion, and 0.42 million technical carats at USD 517 make USD 217.0 million. Cross-check one: 18.84 million exported carats at about USD 60 give about USD 1.13 billion, within 7% of our India-export line at USD 1.21 billion. Cross-check two: the atlas Gujarat 1 to 3 carat cell at USD 96 sits within 1% of half the USD 191 retail acquisition cost. AI drafting and automated checks are used on this report; the research desk chooses sources, builds the model and approves publication under our editorial standards.

Sources

1. De Beers Group De Beers Group announces intention to close Lightbox business (2025)
2. Gemological Institute of America GIA launches updated laboratory-grown diamond services October 1 (2025)
3. Press Information Bureau, Government of India Five-year research grant for lab-grown diamonds to IIT Madras, with LGD export series (2023)
4. US SEC EDGAR Signet Jewelers Form 10-K, fiscal 2025 (2025)
5. ICEX-Invest in Spain Diamond Foundry starts building Cáceres plant (2023)
6. Jewellery Monthly Lab-grown diamond exports surpass natural diamonds by volume in India (GJEPC data) (2026)
7. Jewellery Monthly Lab-grown diamond wholesale prices decline further in 2025 (Edahn Golan / Tenoris data) (2025)
8. Rapaport Lab-grown taking over engagement-ring spending (The Knot 2026 study) (2026)
9. China Daily Lab-grown diamonds look to dazzle again (2023)