Lab Grown Diamond Price Per Carat

This index tracks listed retail prices (not transaction prices) across major U.S. online lab-grown diamond retailers. The October 2026 edition analyzed 237,275 lab-grown diamond listings across seven retailers. Data was collected in the October 24, 2026 cycle (cycle date from the scrape log; the Ritani, Clean Origin and Grown Brilliance files carry a placeholder timestamp, so the files themselves support only the cycle date). With Clarity was pulled in three bands on October 25, Pacific time (file timestamps), the one retailer whose collection date differs. See Coverage this edition.

This edition tracks seven retailers: Ritani, Clean Origin, Grown Brilliance, With Clarity, Blue Nile, Brilliant Earth, and VRAI. The panel is fixed and disclosed for comparability. Any additions, removals, or reclassifications will be explicitly noted in that month's report.

Prices are the publicly visible list price at the time of data collection, including any site-wide or automatic reductions that do not require a membership or promotional code. The index records the price listed on the retailer's page: a sitewide sale already built into the listed prices is included, while code-based discounts, membership discounts, negotiated pricing and crossed-out compare-at prices are excluded. September's Clean Origin figures therefore included its 25% sitewide sale (see Coverage this edition) and October's do not. All prices in USD, excluding sales tax and shipping.

E color, VS1 clarity, round brilliant, Excellent cut, IGI-certified. Three weight cells: 1ct (0.95-1.05ct), 1.5ct (1.45-1.55ct), and 2ct (1.95-2.05ct).

Each published figure is the median total stone price across all qualifying listings within that cell. A minimum of 30 qualifying listings is required for publication. Per-cell sample sizes (n) are visible as tooltips when hovering over any price. Total Stone Price figures in the price table (all cells except VRAI's 1.5ct, corrected in the VRAI note below) are computed as the median price-per-carat for that cell multiplied by the cell's nominal carat weight, not the raw median of actual listing prices; the two differ by up to a few percent (this edition, between 0.0% and 2.6% across the published IGI cells, the largest gap being Clean Origin's 1.5ct cell, $513 published against a raw median of $500). This is a candidate for a deliberate, disclosed methodology change in a future edition, not something being silently recomputed now. Clean Origin 1ct (n=2) falls below the threshold and is not published. Blue Nile 1ct (n=8) falls below the threshold and is not published. Blue Nile 1.5ct (n=7) falls below the threshold and is not published. Blue Nile 2ct (n=9) falls below the threshold and is not published. VRAI 1ct (n=29) falls below the threshold and is not published. VRAI 2ct (n=11) falls below the threshold and is not published.

Both continue to be scraped within three fixed carat bands (0.95-1.09ct, 1.40-1.59ct, 1.90-2.09ct, all colors), the collection method adopted in July. Ritani's October collection (77,299 rows) was within 2% of September's (78,634); its E VS1 IGI round samples were 472, 880 and 734 stones at 1ct, 1.5ct and 2ct (September 504, 975, 798). Grown Brilliance's October collection (51,174 rows, September 53,532) was collected in three band runs; its second and third band runs were first blocked by the site (partial or empty pages), and were re-run in full on a fresh connection, and the blocked partial files are excluded. Its samples were 360, 818 and 815 stones (September 435, 376, 530); its 1ct figure continues to cover 1.00-1.05ct (no listings returned between 0.95 and 0.99ct).

With Clarity's benchmark-band collection was a full capture on all three bands (each band file holds the site's own listing count at collection: 1ct 2,067, 1.5ct 2,673 and 2ct 1,197 listings across all colors and clarities), pulled on October 25. The benchmark cells hold n=523 (1ct), n=756 (1.5ct) and n=268 (2ct). The whole With Clarity collection is 5,937 listings against 8,378 in September. With Clarity is included in every Market Median computation and price range on this page.

Clean Origin's collection returned 13,338 listings against 23,320 in September (-42.8%); round stones fell from 19,029 to 10,505. Its 1.5ct cell (n=127, was 210) publishes at $342 per carat and its 2ct cell (n=181, was 197) at $371; its 1ct cell (n=2) is far below the minimum. The prices of the 10,026 listings present in both collections moved together: 98% are one-third higher than in September (to within half a percent). Clean Origin's September prices carried an 'End of Summer Sale / 25% off sitewide / Prices as marked' banner (Wayback Machine snapshot of its home page, September 11, 2026); October prices on the same stones are 1.3333 times September's, which is that 25% reversed. Clean Origin does not state when the sale ended. September's Clean Origin figures therefore include that sale and October's do not (see Price inputs). Blue Nile's collection was 22,780 listings against 25,859. Its E VS1 Excellent round IGI stones fell to 8, 7 and 9 at 1ct, 1.5ct and 2ct (September 27, 56, 54), while its GIA- and GCAL-graded stones in the same cells were close to unchanged (2ct: 179 GIA in September, 176 in October). With every Blue Nile IGI cell below the minimum, the separate Blue Nile (GIA) reference row used in July and August returns this edition: 2ct $984 per carat (n=176); 1ct (n=0) and 1.5ct (n=3) have no publishable GIA figure. The row is excluded from the Market Median and from every IGI price range, shaded and labeled, and not to be read against the IGI rows.

Four of the six IGI retailers have a published 1ct figure this month (Ritani, Grown Brilliance, With Clarity, Brilliant Earth), the same four as September. Five have a published 1.5ct figure (Ritani, Clean Origin, Grown Brilliance, With Clarity, Brilliant Earth) and five a published 2ct figure (the same five); in September six had both, and Blue Nile's cells at those weights are now below the minimum. VRAI's 1ct cell is no longer published (n=29).

Listings are deduplicated within each retailer by URL. Stones with identical IGI certificate numbers may appear at more than one retailer and are counted as independent listings at each retailer where they appear.

Computed as the median of the per-retailer median prices per carat across all IGI-panel retailers with qualifying (published) data in that cell, rounded, then multiplied by the cell's nominal weight. VRAI and the Blue Nile (GIA) reference row are excluded from this computation (non-IGI, non-comparable). Publication rule, applied from the August edition: a cell's Market Median is published only when every retailer contributing to it also had a published figure in that cell in the prior edition, and the blended month-over-month move agrees with the move of those same retailers to within five percentage points (computed on unrounded percentages); otherwise the blended figure mostly measures who is in the panel and is withheld. All three cells pass this edition. 1ct: the four contributors (Ritani, Grown Brilliance, With Clarity, Brilliant Earth) are the same four as September, so the blended and same-retailer moves are identical; the figure, $544, is 4.7% below September's published $571 (the comparison of the two published figures; on the unrounded per-carat medians used for the rule test the move is -4.8%). 1.5ct and 2ct were withheld in September, so there is no published prior figure to compare against; the test is applied to what the September medians would have been. 1.5ct: all five contributors (Ritani, Clean Origin, Grown Brilliance, With Clarity, Brilliant Earth) published the cell in September; the blended per-carat median moved from $658.5 (six retailers, including Blue Nile) to $448 (-32.0%), and the same five retailers' median moved from $648 to $448 (-30.9%), a difference of 1.1 points; the figure is $672. 2ct: the blended median moved from $707 to $578 (-18.2%) and the same five retailers' from $678 to $578 (-14.7%), a difference of 3.5 points; the figure is $1,156. These are large moves driven by Clean Origin's October prices no longer carrying September's 25% sitewide sale, Grown Brilliance's price cuts and changes in which stones Brilliant Earth lists (see Key Findings), not by the panel changing. Clean Origin's own contribution rose 30% at 1.5ct and 33% at 2ct because September's Clean Origin figures included its 25% sitewide sale and October's do not; the rule treats this as a price move, since it is a change in the listed price and not in which retailers contribute. The published per-retailer figures are shown individually in the price table.

VRAI uses Diamond Foundry proprietary grading exclusively and carries no IGI-certified inventory. Included as a non-comparable reference point. Weight windows: 1ct = 1.0-1.09ct (D-F colors); 1.5ct = 1.6-1.9ct (D-G colors); 2ct = 2.1-2.45ct (D-G colors). VRAI's 1.5ct cell (n=99) is published this edition; its 1ct (n=29) and 2ct (n=11) cells are not. Because VRAI's 1.5ct window (median actual weight 1.74ct) diverges substantially from the nominal 1.5ct label, its published Total Stone Price figure ($2,180) is the true median of actual listing prices for this cell, not median $/ct ($1,250) x 1.5. VRAI's pricing was unchanged again this cycle: of 108 lots present in both the September 17 and October collections within these three windows (matched by product URL), every one carries an identical price to the cent. This index checked the price fields directly against the raw collections.

Historical index figures may not be directly comparable when the benchmark specification or retailer panel changes. Such changes are explicitly noted in the relevant month's report. James Allen was retired from the panel in the June 2026 edition following the closure of its independent storefront. The Ritani and Grown Brilliance carat-band collection is a collection-methodology choice, not a benchmark-specification change; this edition's band request starts at 0.95ct for Ritani, while Grown Brilliance's 1ct coverage is unchanged at 1.00-1.05ct. Month-over-month changes in a cell median mix repricing with changes in which stones are listed; where this index can match listings by URL across months, Key Findings reports both. This edition the Blue Nile (GIA) reference row returns and Market Medians at 1.5ct and 2ct draw on five retailers rather than the six whose cells were published in September.

Rings.com receives no compensation from the retailers included in this index for inclusion or ranking, and no retailer has any editorial control over the methodology or results.