Seven retailers. 259,656 listings. E VS1 Round Excellent IGI.

• $223 to $856 for the same 1ct stone, depending on where you buy. That is the published price range for a 1ct E VS1 IGI round this month, from four of the six IGI retailers (Ritani, Grown Brilliance, With Clarity, Brilliant Earth); Clean Origin and Blue Nile have no published 1ct figure this edition (see the Coverage notes below). At 2ct the published range runs from $496 to $2,730 across five retailers.
• Ritani cut prices, reversing July's increase, with the panel's largest moves at 1ct and 1.5ct. Its 1ct median fell from $295 to $223 per carat (-24%), 1.5ct from $258 to $212 (-18%), and 2ct from $266 to $248 (-7%). Part of the 1ct figure is a coverage change, not a price move: this edition's collection covers the full 0.95-1.05ct cell (July's band began at 1.00ct), and on July's narrower 1.00-1.05ct window Ritani's August median is $245 per carat (n=296), a like-for-like -17%. The 1ct sample is 1,126 stones this month against 302 in July.
• Brilliant Earth moved, and downward, after two editions unchanged at 1.5ct and 2ct. Having held $1,212 per carat at 1.5ct and $1,642 at 2ct in both June and July, it posted -5% at 1ct ($899 to $856), -5% at 1.5ct ($1,212 to $1,151), and -17% at 2ct ($1,642 to $1,365). It remains the IGI panel's premium end in every published cell.
• Grown Brilliance is back at 1ct: $500 per carat (n=795). Its band collection returned 61,542 listings this month against 4,141 in July, nearly fifteen times as many, when the 1ct cell held a single stone and went unpublished. July's reading of that cell as genuine inventory scarcity did not hold: the same collection method, one month later, returned the inventory. July's single 1ct stone was itself listed at $500 per carat, identical to this month's median, and the 1.5ct ($648) and 2ct ($659) medians are within $2 of July's, so July's small sample was not price-biased. Against June's last published 1ct figure ($576), Grown Brilliance is -13% over two months. Note that Grown Brilliance's 1ct figure covers 1.00-1.05ct: its collection returned no listings between 0.95 and 0.99ct in either month.
• Clean Origin's listed inventory contracted sharply, and only its 2ct cell is published: $278 per carat, -34% from July's $421. Clean Origin's own site count for round stones between 0.90ct and 2.50ct was 5,247 at collection (the delivered file holds 5,103 round listings), against 17,764 round listings delivered in July's collection and 3,982 in June's; its E-color round inventory in the 1ct cell fell from 2,546 listings to 51 (one of them VS1), so the 1ct and 1.5ct cells (n=1 and n=24) are not published. This closes July's open question about Clean Origin's June-to-July inventory jump only partially: the listed count swings widely month to month, and this index reports the count without knowing the cause.
• Blue Nile has no published IGI cell this month, so a labeled GIA reference row is shown; VRAI repriced its inventory upward. Blue Nile's E VS1 IGI cells hold 18, 5 and 27 listings on a full-inventory pull of similar size to July's (28,836 listings against 29,857). Its 1ct cell was equally thin in July (n=18): genuinely thin E VS1 IGI inventory. Its 1.5ct and 2ct cells (47 and 54 in July) thinned because a larger share of its E-color round inventory now carries GCAL or GIA reports rather than IGI, and VS1 remains a minority clarity grade; a share shift, not a collection issue. Because Blue Nile is otherwise absent from the table, its GIA-graded E VS1 Excellent stones are shown as a separate reference row, the same treatment VRAI gets: $988 per carat at 2ct (n=191), no publishable GIA figure at 1ct (n=0) or 1.5ct (n=3). That row is not part of the Market Median or the IGI price ranges, and it is not comparable to the IGI rows: GIA and IGI reports are different grading regimes, and in this month's data GIA-graded stones list above IGI-graded ones at every panel retailer where both appear in a cell; Blue Nile itself is the caveat to that pattern: its GIA and IGI 2ct E VS1 medians tracked within $1 per carat of each other from April through July (identical in April and July, $1 apart in May and June) before separating by $165 in August, $988 GIA on 191 stones against $823 for the 27 IGI stones, a sample too small to publish and too small to say whether that separation is real. VRAI, tracked as a non-IGI reference point, raised prices across its inventory: the 413 lots listed in both months rose a median 76% (on VRAI's own cell windows: +33% for the 18 lots in the 1ct window, 1.0-1.09ct D-F, and +69% for the 62 lots in the 1.5ct window, 1.6-1.9ct D-G). Its 1ct cell is published at $1,583 per carat (n=36), +34% against July's unpublished $1,180 (n=29) and +37% against June's last published $1,159; its 1.5ct cell's median stone price is $2,160 (1.6-1.9ct window, median 1.75ct) against $1,229 in July. This index verified the change against VRAI's own listings; it is VRAI's pricing, not a currency or collection effect.
• With Clarity is essentially flat, and only the 1.5ct Market Median is published. With Clarity's collection was blocked at the first request from the home connection and completed the same evening from three successive mobile-network IPs, each blocked in turn after roughly 200 requests: $628 per carat at 1ct (n=536, full capture, +$8 versus July), $691 at 1.5ct (n=910, a partial capture of 85% of the band collected in price-ascending order, so a floor on the true median; July's $698 was a 74% capture of the same kind), and $694 at 2ct (n=694, full capture, -$34). A Market Median is published this month only where every retailer in the cell also had a published figure in July and the blended move agrees with the same-retailers move to within five percentage points. The 1.5ct Market Median passes: $1,005 (Ritani, Grown Brilliance, With Clarity, Brilliant Earth) against July's six-retailer $1,011, -0.6% blended and -0.6% on the same four retailers. The 1ct cell fails the first test because Grown Brilliance was not published in July (a blended $564 against July's unpublished $481; the three retailers in both months, Ritani, With Clarity and Brilliant Earth, moved +1.3% together, $620 to $628). The 2ct cell fails the second test by the narrowest margin: the blended figure ($1,318, five retailers, against July's six-retailer $1,388, -5.0%) sits 5.04 points from the same five retailers' move (0.0%, $1,318 to $1,318, Blue Nile having dropped out), so it is withheld rather than the rule bent; the per-retailer 2ct figures are shown individually.

Scope. This index tracks listed retail prices (not transaction prices) across major U.S. online lab-grown diamond retailers. The August 2026 edition analyzed 259,656 lab-grown diamond listings across seven retailers. Data was collected on August 29, 2026 (With Clarity in three supplemental pulls the same evening, Pacific time; see Coverage this edition).

Retailer panel. 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.

Price inputs. 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. Excluded: promotional codes, membership discounts, negotiated pricing, strikethrough compare-at prices. All prices in USD, excluding sales tax and shipping.

Benchmark specification. 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).

Statistical method. 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% and 3.9% across the published IGI cells, the largest gap being Grown Brilliance's 1ct cell, $500 published against a raw median of $520). This is a candidate for a deliberate, disclosed methodology change in a future edition, not something being silently recomputed now. Clean Origin 1ct (n=1) falls below the threshold and is not published. Clean Origin 1.5ct (n=24) falls below the threshold and is not published. Blue Nile 1ct (n=18) falls below the threshold and is not published. Blue Nile 1.5ct (n=5) falls below the threshold and is not published. Blue Nile 2ct (n=27) falls below the threshold and is not published. VRAI 2ct (n=14) falls below the threshold and is not published.

Coverage this edition: Ritani and Grown Brilliance. Both were scraped within three fixed carat bands rather than a full-inventory census, the collection method adopted in July to avoid the multi-hour timeouts and rate-limit hangs both retailers have produced. The band requests now start at 0.95ct (0.95-1.09ct, 1.40-1.59ct, 1.90-2.09ct, all colors). For Ritani this covers the published 1ct cell (0.95-1.05ct) in full; July's 1.00-1.09ct band covered only its upper half. This raises Ritani's 1ct sample from 302 to 1,126 stones and contributes part of the reported 1ct decline (see Key Findings for the like-for-like figure on July's window). Grown Brilliance returned no listings between 0.95 and 0.99ct in either month, so its 1ct figure covers 1.00-1.05ct; this index does not know whether Grown Brilliance stocks stones in that range. Grown Brilliance's collection returned 61,542 listings against 4,141 in July, restoring its 1ct cell (n=795, unpublished in July at n=1); July's report attributed that thin cell to genuine inventory scarcity on the strength of a live re-scrape that reproduced the same small set, and this month's return from the same method, nearly fifteen times larger, shows that reading was at best short-lived. This index does not know whether Grown Brilliance restocked or whether its July inventory was under-served to collection; July's single 1ct stone was listed at $500 per carat, identical to this month's median, and the 1.5ct and 2ct medians are within $2 of July's either way.

Coverage this edition: With Clarity. With Clarity's benchmark-band collection was blocked at the first request (HTTP 403) from the home connection by the site's access restrictions on high-volume data collection, from an IP address that had not queried the site since July 25. It was completed the same evening (August 29, Pacific time) in three supplemental pulls from successive mobile-network IP addresses, each of which the site blocked in turn after roughly 200 requests. The 1ct band (2,330 of 2,330 listings the site reported) and the 2ct band (2,884 of 2,884) are full captures. The 1.5ct band captured 3,940 of 4,613 listings (85%) before its IP was blocked; because the site serves listings in ascending price order, the uncaptured 15% are the highest-priced listings in the band, and the published 1.5ct figure ($691 per carat, n=910) is therefore a floor on the true median, disclosed as a partial capture in the price table. An earlier 34% capture of the same band from the first mobile IP is entirely contained in the 85% capture (1,580 of 1,580 listings matched by URL). July's 1.5ct figure ($698) was a 74% capture of the same kind. With Clarity is included in every Market Median computation and price range on this page.

Coverage this edition: Clean Origin and Blue Nile. Clean Origin's full-inventory collection returned 6,886 listings against 26,972 in July; its own site count for round stones between 0.90ct and 2.50ct was 5,247 at collection, the delivered file holds 5,103 round listings (17,764 in July's collection, 3,982 in June's), and wider site queries (7,715 between 0.50ct and 3.00ct, 10,367 between 0.30ct and 5.00ct) confirm the contraction is in the listed inventory, not in the collection. Its E-color round inventory in the 1ct cell fell from 2,546 listings to 51 (one VS1), so the 1ct (n=1) and 1.5ct (n=24) cells are not published; the 2ct cell (n=187) is. Blue Nile was a full-inventory pull as usual (28,836 listings, against 29,857 in July) and its E-color round inventory is of similar size to July's. Its 1ct E VS1 IGI cell is thin for the second month (n=18 in both), genuinely thin inventory; its 1.5ct and 2ct cells (n=5 and 27, against 47 and 54 in July) thinned because a larger share of that inventory now carries GCAL or GIA reports rather than IGI, and VS1 remains a minority clarity grade behind VVS2. No Blue Nile cell is published this edition. Because Blue Nile is otherwise absent from the price table this edition, a separate reference row, Blue Nile (GIA), shows its E VS1 Excellent round stones carrying GIA reports: 2ct $988 per carat (n=191); 1ct (n=0) and 1.5ct (n=3) have no publishable GIA figure. The row uses the same non-comparable treatment as VRAI: excluded from the Market Median and from every IGI price range on this page, shaded and labeled in the table, and not to be read against the IGI rows, since GIA and IGI reports are different grading regimes and, in this month's data, GIA-graded stones list above IGI-graded ones at every panel retailer where both appear in a cell. Blue Nile itself is the caveat: its GIA and IGI 2ct E VS1 medians tracked within $1 per carat of each other from April through July (IGI $1,034, $1,035, $906, $905; GIA $1,034, $1,034, $905, $905) and separated by $165 in August ($988 GIA on 191 stones against $823 on 27 IGI stones), where the IGI side is a sample the index does not publish and cannot say is representative. The row's history is back-filled from the same monthly collections (2ct: $2,068 in April and May, $1,810 in June and July, $1,976 in August; 1ct and 1.5ct GIA cells were below the minimum in every month). The reference row appears only in editions where Blue Nile's IGI cells are below the minimum; Blue Nile's IGI figures remain the benchmark series.

Coverage this edition: what is published at 1ct. Four of the six IGI retailers have a published 1ct figure this month (Ritani, Grown Brilliance, With Clarity, Brilliant Earth), the same number as July with a different composition (Clean Origin out, Grown Brilliance in). The 1ct Market Median is not published this edition, see the Market Median entry below; the four published figures are shown individually in the price table. The 1.5ct Market Median draws on the same four retailers. Five IGI retailers have a published 2ct figure (Ritani, Clean Origin, Grown Brilliance, With Clarity, Brilliant Earth); the 2ct Market Median is not published, see below.

Deduplication. 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.

Market Median. 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 this 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. 1.5ct passes and is published: $1,005, from Ritani, Grown Brilliance, With Clarity, and Brilliant Earth, against July's six-retailer $1,011, -0.6% blended and -0.6% on the same four retailers ($1,011 to $1,005). With Clarity's 1.5ct input ($691 per carat) is an 85% capture and a floor, as July's ($698) was a 74% capture; if every uncaptured listing were pricier than every captured one, With Clarity's true median would be about $707 and the Market Median about $1,017, and the July-to-August move would be -0.2% instead of -0.6%: the level is understated by at most about 1.2%, the direction and size of the move are not affected. 1ct fails the first test: Grown Brilliance had no published 1ct figure in July (a blended $564 would compare Ritani, Grown Brilliance, With Clarity, and Brilliant Earth with July's unpublished $481 from Ritani, Clean Origin, With Clarity, and Brilliant Earth; the three retailers in both months, Ritani, With Clarity, and Brilliant Earth, moved +1.3% together, $620 to $628). 2ct fails the second test by 0.04 points: the blended figure ($1,318, from Ritani, Clean Origin, Grown Brilliance, With Clarity, and Brilliant Earth, against July's six-retailer $1,388, -5.0%) differs by 5.04 points from the move of those same five retailers in both months (0.0%, $1,318 to $1,318), Blue Nile having dropped out; the rule is applied as written rather than bent to a borderline case. Those figures are computed here only to show why the blended numbers are not published; the published per-retailer figures are shown individually in the price table instead.

VRAI. 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 1ct (n=36) and 1.5ct (n=95) cells are published this edition; its 2ct cell (n=14) is not. The 1ct figure is median $/ct x 1 ($1,583; the raw median listing price in that window, median weight 1.04ct, is $1,650). Because VRAI's 1.5ct window (median actual weight 1.75ct) diverges substantially from the nominal 1.5ct label, its published Total Stone Price figure ($2,160) is the true median of actual listing prices for this cell, not median $/ct ($1,250) x 1.5. VRAI repriced its inventory upward between the July 23 and August 29 collections: of the 413 lots listed in both, the median same-lot price change is +76% (carat and color unrestricted); restricted to VRAI's own cell windows as defined above it is +33% for the 18 lots in the 1ct window and +69% for the 62 lots in the 1.5ct window. This index checked that the change is not a currency or collection artifact (VRAI's listing API returns the same price for the same lot regardless of the requesting location, and the change is not a uniform multiplier); it is VRAI's own pricing.

Comparability. 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, which brings Ritani's 1ct cell to full coverage and affects its 1ct sample as described above, while Grown Brilliance's 1ct coverage is unchanged at 1.00-1.05ct. With Clarity's 1.5ct figure is a partial capture (85%) this edition, as July's was (74%), and is a floor on the true median; see Coverage this edition.

Independence. 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.