Three tables, free to download as CSV or JSON. Every issue keeps its own file at a fixed address, and every file's SHA-256 is in the manifest, so a figure you quote can be checked later against the exact file it came from.
Lab-grown diamond benchmark price list
US$ per carat for loose lab-grown diamonds, round basis, by carat band, colour and clarity: 800 figures an issue, each computed by the GDCS formula.
Latest · issue 2026-10-02 CSV · JSON · Read it as a page
Every issue: 2026-10-02
Licence
Free to use, share and adapt, commercial use included, with credit and a link: CC BY 4.0. The price level is fitted to The Diamond Price's Diamond Price Index, used under CC BY 4.0; credit it as well. GDCS adapts it: the rows are fitted to the GDCS formula and none of the data set's own figures is reprinted.
How to cite
GDCS, Association for Intelligent Diamond International. (2026). GDCS Lab-Grown Diamond Benchmark Price List, issue 2026-10-02 [Data set]. https://gdcs.ai/prices/2026-10-02/
A sentence you can quote
1.00–1.49 ct round, F, VS1: US$ 740 per carat (GDCS lab-grown diamond benchmark, issue 2026-10-02). Every figure is computed by the GDCS formula; none is a seller's price.
What each column means
| Column | Meaning |
|---|
issue | Issue date of the price list. |
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rules | Version of the GDCS rules that produced it; the rules file is at /rules/.json. |
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band_from_ct | Lower edge of the carat band. |
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band_to_ct | Upper edge of the carat band. |
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carat_used | The carat weight inside the band at which the figure is computed. |
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colour | Colour grade, GDCS/T—2027. |
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clarity | Clarity grade, GDCS/T—2027. |
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usd_per_ct | Benchmark price in US$ per carat for a loose round stone at the base cut, before any brand premium. |
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Brand records
One row per company in the AIDI Trust Index: tier, whether a product fact is independently confirmed, the best evidence in each of seven areas, and the premium GDCS applies.
Latest · issue 2026-09 CSV · JSON · Read it as a page
Every issue: 2026-09
Licence
Free to quote and reuse for reporting, research, teaching and NGO work, with credit and a link. A company that wants to show its own standing in its own advertising or packaging needs the display licence at aidi.org/cite.
How to cite
GDCS, Association for Intelligent Diamond International. (2026). GDCS Brand Records (AIDI Trust Index), issue 2026-09 [Data set]. https://gdcs.ai/brands/
A sentence you can quote
Of the 500 companies in AIDI Trust Index 2026-09, 124 have at least one product fact checked by someone independent (GDCS brand records).
What each column means
| Column | Meaning |
|---|
issue | AIDI Trust Index issue the record is read from. |
|---|
brand | Company or brand name. |
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slug | Address key: gdcs.ai/brand// and aidi.org/trust-index//. |
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tier | Trust Index tier: Diamond, Gold, Silver, Bronze or Under review. |
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product_fact_confirmed | yes if at least one product fact is checked by someone independent; the premium opens only then. |
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premium_pct | Premium in per cent that GDCS adds to the benchmark for this company's stones. |
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hq | Where the company is based. |
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segment | What the company does: brand, retailer, maker, lab (lab-grown producer) or miner. |
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carbon_energy | Best evidence found in this area: independent, own_report, not_found or contradicted. |
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water_chemicals | Best evidence found in this area: independent, own_report, not_found or contradicted. |
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people_labour | Best evidence found in this area: independent, own_report, not_found or contradicted. |
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provenance | Best evidence found in this area: independent, own_report, not_found or contradicted. |
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reuse_recycling | Best evidence found in this area: independent, own_report, not_found or contradicted. |
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certificates_reports | Best evidence found in this area: independent, own_report, not_found or contradicted. |
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nature | Best evidence found in this area: independent, own_report, not_found or contradicted. |
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gdcs_url | This company's page on gdcs.ai. |
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trust_index_url | This company's full record on aidi.org. |
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Grey List
Companies, mostly lab-grown growers, cutters and jewellers in India and China, where a check found no sustainability disclosure at all; one row per company, with the date it was checked.
Latest · issue 2026-11 CSV · JSON · Read it as a page
Every issue: 2026-11 · 2026-10
Licence
Free to use, share and adapt, commercial use included, with credit and a link: CC BY 4.0.
How to cite
GDCS, Association for Intelligent Diamond International. (2026). GDCS Grey List, issue 2026-11 [Data set]. https://gdcs.ai/grey-list/
A sentence you can quote
GDCS Grey List, issue 2026-11: of 533 companies checked, 331 had no sustainability disclosure the check could find.
What each column means
| Column | Meaning |
|---|
issue | Grey List issue. |
|---|
rules | Version of the sealed Grey List rules the issue was checked under; at /rules/.json. |
|---|
name | Company name as registered or as it trades. |
|---|
name_local | Name in the local script, where known. |
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country | Country, ISO 3166-1 alpha-2. |
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city | City, where known. |
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kind | grower_cutter, brand_retailer or maker (jewellery manufacturer or trader). |
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checked | Date the check ran. |
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pages | Pages of the company's own website the check read; 0 when it has none. |
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has_website | yes, no, or blank where the issue's rules did not record it. |
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record | Fingerprint of the evidence on file for this row. |
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Every file, with its size and SHA-256