The Lab Grown Diamond Market Report 2026

Lab grown diamond share is reported as a single percentage, and that is the most common error in the entire category. Share by units and share by dollars are not the same number, and they are not close. Per carat prices collapsed while unit sales climbed, so volume share races ahead of value share. Any report that blends them into one figure is wrong before it starts.

Two anchors set the frame. By units, lab grown reached 61 percent of US engagement rings in 2025.¹ By value, lab grown holds roughly 21 percent of the global diamond market, up from about 14 percent in 2023.⁸ The dollar figure is capped, and staying capped, because wholesale prices fell about 26 percent in 2025 alone and roughly 86 to 90 percent cumulatively since tracking began in 2018.²⁴

This is why any claim of a lab grown value growth rate above 13 percent a year does not hold. A double digit dollar growth rate cannot coexist with an 86 to 90 percent price collapse unless unit volume more than offsets it. The category grows in units. It does not grow in dollars at anything like the rate the syndicated forecasts imply. We read this in the lab grown price collapse analysis, and the market data confirms it.

The total jewelry market has no single agreed size, because firms define the market differently. Present it as a range. A fine jewelry cluster sits near USD 243 billion for 2025, and an all jewelry cluster sits near USD 382 billion, roughly USD 130 billion apart on scope alone.⁹⁸ The growth rate is the well corroborated part: about 4.7 to 5.5 percent a year to 2030 across several firms.

The three geographies do not report the same way, so the table below keeps each figure with its confidence. The United States has the deepest data, the world sits on syndicated estimates, and Canada is the thinnest of the three.

The global lab grown diamond market itself clustered tightly at about USD 28 to 30 billion in 2025 across four firms.⁹¹⁴ Their forward growth rates are the part to distrust, for the reason set out above.

In the United States, 61 percent of engagement rings had a lab grown center stone in 2025. That is a 239 percent rise since 2020, on a study of 10,474 couples, with an average lab grown spend of USD 4,600 at 1.9 carats.¹ The trajectory is the cleanest series in the dataset.

Now the value caveat, in one line. That 61 percent is a volume ceiling. Measured by insured appraisal value, lab grown reads lower, near 47.7 percent of engagement rings and 42.1 percent of all diamond jewelry.³ Natural still holds a larger share of engagement ring dollars than of units, because a mined ring averaged about USD 7,600 against USD 4,900 for lab grown.¹ The sources diverge on what they measure, survey versus insured appraisal, not on whether the shift is real.

Buyer behaviour explains the rest. Buyers hold their budget and buy bigger, which is why the average lab grown centre stone reached 1.9 carats. The full picture sits in the lab grown diamond statistics for 2026.

Yes by units, and roughly flat to modest by dollars. US jewelry sales grew 5.6 percent in 2025 on transaction data, with finished jewelry up 7.5 percent, driven by higher spend per item as unit volumes softened.² Loose lab grown units rose while loose lab grown revenue slipped, the signature pattern of a category expanding in count and contracting in price.

The structural signals point the same way. De Beers closed its Lightbox lab grown brand in May 2025 after the unit lost USD 101.3 million in 2023, framing the exit as a recommitment to natural.⁴ Signet announced in March 2026 that it would fold James Allen into Blue Nile, retiring one of the best known online diamond banners even as lab grown volume expanded across its chains.⁵ These are the moves of a maturing category where scale players rationalise overlapping brands. We track the wider shakeout in the De Beers and diamond industry analysis.

From September 2026, industry body CIBJO mandates the single term "synthetic" for man made stones, reserving the 4Cs for natural.¹¹ A terminology change, but a signal that the trade is drawing hard lines as volumes settle.

There is no published national figure. That is the honest answer, and it is the most useful one in this report. No firm publishes a measured Canadian lab grown engagement ring share, so any precise Canadian percentage is an inference from US data, never a Canadian statistic. The defensible read is that Canadian adoption is high and rising, and likely within a few points of the US, but unmeasured.

The total Canadian jewelry market is about USD 4.39 billion in consumer spend, or about CAD 3.6 billion in jewellery store revenue across 2,980 stores, a channel coverage gap rather than a contradiction.⁸¹³ The hardest local signal on adoption is a single named retailer: a Toronto store reports natural diamonds down to roughly 3 to 4 percent of its business, from 100 percent before lab grown entered, which implies about 96 percent lab grown.¹² One store, not a national average, but a concrete on the record data point.

The strategic Canadian story is on the supply side. The mined Canadian diamond base is closing. National production fell to 13.3 million carats worth CAD 1.47 billion in 2024, down 17 percent in volume and 30 percent in value.⁶ Diavik delivered its final production on March 26 2026, and Rio Tinto has fully exited diamond mining.⁷ Ekati suspended a sub economic pit and entered creditor protection, and Gahcho Kue is estimated end of life around 2031.¹² The romantic ethically mined Canadian diamond is running out of physical inventory.

That is the opening. As the mined Canadian stone becomes scarce, lab grown becomes the modern Canadian diamond: a Canadian brand, globally sourced, IGI certified. There is a structural footnote worth stating plainly. US import tariffs are multi lane, court challenged, and have shifted repeatedly through 2026, so this report quotes no single rate. The constant, independent of any rate, is mechanical: a US import tariff cannot attach to a domestic Canadian purchase. A Canadian brand selling to Canadians for Canadian delivery is structurally insulated from that regime. We cover the home market in the Canadian lab diamond pricing report.

This report was built from three parallel research passes, one per geography, compiled in August 2026 and verified against named 2025 and 2026 sources. Where firms disagree, the range is shown rather than a false single point. The figures fall into three tiers.

The gaps are stated as data, not smoothed over. Canada has no published lab grown share time series, no clean engagement ring market size in Canadian dollars, and no dated Canadian retailer mix beyond the single Toronto data point. Where a Canadian number would have to be borrowed from the US, this report says so rather than dressing a US figure as Canadian.