Company lists · Data refreshed November 2026
Top 25 Gemstone certification services worldwide
RevenueBase identified 845 company matches for gemstone certification services worldwide as of November 2026 and tracks 8,111 professional contacts across them, including 2,027 with verified work emails. India is the largest market and Jaipur the largest hub.
This list covers company matches for gemstone certification services worldwide, found by RevenueBase SmartSearch using the meaning of business descriptions in its company graph at Exact. Ranked by professionals tracked, largest first. Rows show recorded descriptions where available, Exact search membership and the snapshot date. Data refreshed November 6, 2026. Country and city lists for gemstone certification services follow the table.
Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase SmartSearch, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.
The 25 largest gemstone certification services worldwide
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 385 contacts → | ||||
Exact match “IGI, a Blackstone portfolio company, is the world’s largest independent provider of gemological services.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase | |||||
| 2 | 260 contacts → | ||||
Exact match “HRD Antwerp is the leading authority when it comes to Diamond Grading, Jewellery Grading and Education.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase | |||||
| 3 | 193 contacts → | ||||
Exact match “Peace of mind, Assured.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase | |||||
| 4 | 161 contacts → | ||||
Exact match “Gemological Science International (GSI) is one of the largest gemological laboratories with 13 offices in the United States, India, UAE, Hong Kong and Thailand.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase | |||||
| 5 | 127 contacts → | ||||
Exact match “GemPundit is one of the leading providers of Luxury, Precious & Semi-Precious Gemstones.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase | |||||
| 6 | 127 contacts → | ||||
Exact match “A dream company started by three visionaries; Arvind Shah, Arun Shah and Dilip Shah in 1985, was then strengthened by Vasant Shah, Pravin Shah and Dilip Soni, bringing together…” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase | |||||
| 7 | 83 contacts → | ||||
Exact match “GemsNY is your trusted source for untreated, certified natural color gemstones and custom fine jewelry.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase | |||||
| 8 | 66 contacts → | ||||
Exact match “The Birmingham Assay Office was founded in 1773 to provide Assaying (testing) and Hallmarking of precious metal items (Gold, Silver, Platinum and Palladium) as required by the…” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase | |||||
| 9 | 61 contacts → | ||||
Exact match “IDT is among the premier networks of Gemological Laboratories, which empowers and enables jewellers, jewellery brands, manufacturers, wholesalers, end-use customers and the masses…” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase | |||||
| 10 | 52 contacts → | ||||
Exact match “we are manufacturer of GIA / IGI / AGA certified diamonds from 0.30cts to 15 carats.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase | |||||
| 11 | 51 contacts → | ||||
Exact match “Creating and supporting gemmologists since 1908.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase | |||||
| 12 | 50 contacts → | ||||
Exact match “America's Diamond Specialist - Memo and Stock Quality, attention to detail, honesty, fairness, and on-time delivery.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase | |||||
| 13 | 48 contacts → | ||||
Exact match “As a reflection of Bahrain’s ancient pearling history and the strong desire to protect this heritage, the Bahrain Institute for Pearls & Gemstones (DANAT) was established as the…” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase | |||||
| 14 | 29 contacts → | ||||
Exact match “The Swiss Gemmological Institute, part of the Swiss Foundation for the Research of Gemstones (SSEF: Schweizerische Stiftung für Edelstein-Forschung) was founded by trade…” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase | |||||
| 15 | 28 contacts → | ||||
Exact match “The Gemmological Association of Australia (GAA) is Australia’s long established gemmological educator.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase | |||||
| 16 | 26 contacts → | ||||
Exact match “GGTL Laboratories is the merging of two laboratories: GemTechLab, founded in 1996 by Franck Notari in Geneva, Switzerland and GEMLAB (Liechtenstein), founded in 1996 by Thomas…” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase | |||||
| 17 | 25 contacts → | ||||
Exact match “ICA | GemLab is an expert in identification, origin determination, and treatment detection for colored gemstones.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase | |||||
| 18 | 24 contacts → | ||||
Exact match “Yolculuğumuz, 10 yılı aşkın süredir yüzbinlerce pırlantayı derecelendiren uzman gemologların bir araya gelmesiyle başladı.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase | |||||
| 19 | 21 contacts → | ||||
Exact match “We specialize in GIA certified diamonds with a choice of 6,500+ stones with AI technology of Auto Answering and 24*7 @Bot helpline to serve all our customers regardless of time…” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase | |||||
| 20 | 20 contacts → | ||||
Exact match “The Gübelin Gem Lab was founded in 1923 as a small gemmological laboratory to examine and determine the authenticity of the stones used in Gübelin’s jewellery.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase | |||||
| 21 | 20 contacts → | ||||
Exact match “The Asian Institute of Gemological Sciences (AIGS) was founded in 1978 as South East Asia’s first international gemological education facility.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase | |||||
| 22 | 19 contacts → | ||||
Exact match “At ZCOVA, we modernise the way consumers purchase Diamonds, Coloured Gemstones, and Jewellery.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase | |||||
| 23 | 19 contacts → | ||||
Exact match “Um ecossistema 360º de serviços especializados para o mercado de joias, gemas e metais preciosos.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase | |||||
| 24 | 17 contacts → | ||||
Exact match “Maison PIAT specializes in the search and cut of natural colored and non-treated gemstones.” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase | |||||
| 25 | 17 contacts → | ||||
Exact match “Labon Diamonds” Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase | |||||
RevenueBase SmartSearch
Describe a niche business in your own words. RevenueBase SmartSearch compares the meaning of your description with company business descriptions compiled in the RevenueBase company graph. Exact, Similar, Related and Broad control how closely companies must fit.
This list uses Exact for “gemstone certification services”. Each Exact match badge shows membership in that saved search; it is not an individual similarity score or a service-quality rating. Recorded descriptions are shown where available.
Showing 25 of 845 gemstone certification services worldwide
See the full list, filter by size, metro and specialty, and access 2,027 tracked professional contacts with verified work emails. Direct dials are available where recorded.
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Gemstone certification services worldwide at a glance
As of Nov 6, 2026Companies by employee count
Email recency is reported on each country list linked below.
How this list was built
The recorded descriptions help you assess these company matches. Check a company’s website for its current services and locations.
- Source
- The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase SmartSearch, the natural-language company search available to every RevenueBase user.
- Coverage
- Every country. Country and city lists for gemstone certification services are linked below.
- What qualifies
- Company records worldwide whose business descriptions match “gemstone certification services” by meaning at the Exact setting. Descriptions are compiled in the RevenueBase company graph from public websites, profiles and company information where available; they are not guaranteed quotations from the company's website.
- RevenueBase SmartSearch
- Describe a niche company in your own words to find businesses by meaning. Exact, Similar, Related and Broad control the breadth of RevenueBase SmartSearch. This saved list uses Exact. Each row's Exact match badge shows inclusion in that search, not an individual score or a service-quality judgment.
- Public preview
- The public preview omits records without a verified work email. Dataset totals and geographic summaries describe the full matched records before these preview filters.
- Match quality
- RevenueBase's August 25, 2026 study assessed 4,198 description/company pairs across matching settings. The publisher reports 86% good or better at Exact. This evaluates the method across queries; it does not audit this individual list. Recorded company descriptions, where available, help you judge each match yourself. Read the full methodology: how the lists are built and what the study measures.
- Ranking
- Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
- Verification
- Every displayed company carries at least one verified work email. RevenueBase tracks 2,027 professional contacts with verified work emails across the full matched dataset. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
- Refresh
- This page's figures were pulled from the company graph on November 6, 2026. Lists refresh periodically as the graph is re-checked.
- Record context
- Company records and descriptions can change. Check the company's website for its current services and locations.
Gemstone certification services by location
3 lists · largest firstEvery Gemstone certification services list RevenueBase publishes, by country and city. Counts are matching companies in each list as of its own refresh date.
Countries
- Gemstone certification services based in India191
- Gemstone certification services based in the United States116
Cities
Frequently asked
What is RevenueBase SmartSearch?
RevenueBase SmartSearch finds niche companies by the meaning of their business descriptions in the RevenueBase company graph. Exact, Similar, Related and Broad control how closely companies must fit your description. This list uses Exact for “gemstone certification services”; each Exact match badge shows search membership, not an individual similarity or quality score.
How many gemstone certification services are there worldwide?
RevenueBase identified 845 company matches for gemstone certification services worldwide as of November 2026, using the meaning of business descriptions at Exact. This is the recorded matched set in the RevenueBase company graph.
What is the largest company on this list?
International Gemological Institute - USA tops the displayed preview by professional contacts tracked in RevenueBase. Recorded headquarters appear in the company rows.
Which country has the most gemstone certification services?
India leads with 191 companies, followed by the United States (116). Every gemstone certification services list by country and city is linked on this page.
Which city has the most gemstone certification services?
Jaipur leads with 62 company records, followed by New York (34) and Bangkok (25).
How do I get contact information for these companies?
A free RevenueBase account lets you run this exact search and work limited free results with 500 credits to start. Upgrading provides access to the 2,027 professional contacts with verified work emails tracked across these 845 companies; direct dials are available where recorded.
How current is this list?
The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on November 6, 2026.
Ready to reach these companies? Verified emails and direct dials for all 845 gemstone certification services worldwide. Start with a free account, no credit card.
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About this data
RevenueBase is a B2B data infrastructure company. Its company graph covers 60 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph with RevenueBase SmartSearch, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.
More company lists
Company intelligence · public preview
Top 25 gemstone certification services worldwide
Find companies in any niche.
Describe the businesses you want in your own words. RevenueBase SmartSearch matches company descriptions by meaning.
RevenueBase records 845 matching company records for gemstone certification services worldwide, with 8,111 tracked contacts and 2,027 verified work emails.
This public preview shows 25 selected records ordered by tracked contacts. RevenueBase SmartSearch finds company descriptions that match by meaning at Exact. Snapshot: November 6, 2026.
RevenueBase compiles business descriptions for niche-company discovery; each row shows a recorded excerpt where available. Adapt this search to find the companies and contacts you want.
Top 25 gemstone certification services worldwide
The public list shows selected company records with contact and verified-email coverage. Reported employee bands provide separate company-size context.
| # | Company | Headquarters on record | Reported employees | RevenueBase SmartSearch | Tracked contacts |
|---|---|---|---|---|---|
| 1 | HQ: New York, CA, United StatesReported employees: 501-1,000 | New York, CA, United States | 501-1,000 | Exact match | 385 contacts → |
“IGI, a Blackstone portfolio company, is the world’s largest independent provider of gemological services.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 2 |  HRD Antwerphrdantwerp.comHQ: Antwerp, BelgiumReported employees: 201-500 | Antwerp, Belgium | 201-500 | Exact match | 260 contacts → |
“HRD Antwerp is the leading authority when it comes to Diamond Grading, Jewellery Grading and Education.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 3 |  SGL Labssgl-labs.comHQ: London, United KingdomReported employees: 201-500 | London, United Kingdom | 201-500 | Exact match | 193 contacts → |
“Peace of mind, Assured.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 4 |  Gemological Science International GSIgemscience.netHQ: Manhattan, United StatesReported employees: 51-200 | Manhattan, United States | 51-200 | Exact match | 161 contacts → |
“Gemological Science International (GSI) is one of the largest gemological laboratories with 13 offices in the United States, India, UAE, Hong Kong and Thailand.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 5 |  gempundit.comgempundit.comHQ: Gurgaon, IndiaReported employees: 201-500 | Gurgaon, India | 201-500 | Exact match | 127 contacts → |
“GemPundit is one of the leading providers of Luxury, Precious & Semi-Precious Gemstones.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 6 |  Ankit Gemsankitgems.comHQ: Mumbai, IndiaReported employees: 1,001-5,000 | Mumbai, India | 1,001-5,000 | Exact match | 127 contacts → |
“A dream company started by three visionaries; Arvind Shah, Arun Shah and Dilip Shah in 1985, was then strengthened by Vasant Shah, Pravin Shah and Dilip Soni, bringing together…” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 7 |  Gemsnygemsny.comHQ: Fort Lee, NJ, United StatesReported employees: 51-200 | Fort Lee, NJ, United States | 51-200 | Exact match | 83 contacts → |
“GemsNY is your trusted source for untreated, certified natural color gemstones and custom fine jewelry.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 8 |  Birmingham Assay Officetheassayoffice.comHQ: Birmingham, United KingdomReported employees: 51-200 | Birmingham, United Kingdom | 51-200 | Exact match | 66 contacts → |
“The Birmingham Assay Office was founded in 1773 to provide Assaying (testing) and Hallmarking of precious metal items (Gold, Silver, Platinum and Palladium) as required by the…” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 9 |  IDT Gemological Laboratories Worldwideidtworldwide.comHQ: United StatesReported employees: 51-200 | United States | 51-200 | Exact match | 61 contacts → |
“IDT is among the premier networks of Gemological Laboratories, which empowers and enables jewellers, jewellery brands, manufacturers, wholesalers, end-use customers and the masses…” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 10 |  Pansuriya Impex HK LTDpansuriyaimpex.comHQ: IndiaReported employees: 1,001-5,000 | India | 1,001-5,000 | Exact match | 52 contacts → |
“we are manufacturer of GIA / IGI / AGA certified diamonds from 0.30cts to 15 carats.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 11 |  Gem-Agem-a.comHQ: London, United KingdomReported employees: 11-50 | London, United Kingdom | 11-50 | Exact match | 51 contacts → |
“Creating and supporting gemmologists since 1908.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 12 |  RDI Diamonds INCrdidiamonds.comHQ: Rochester, NY, United StatesReported employees: 51-200 | Rochester, NY, United States | 51-200 | Exact match | 50 contacts → |
“America's Diamond Specialist - Memo and Stock Quality, attention to detail, honesty, fairness, and on-time delivery.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 13 | HQ: Manama, BahrainReported employees: 11-50 | Manama, Bahrain | 11-50 | Exact match | 48 contacts → |
“As a reflection of Bahrain’s ancient pearling history and the strong desire to protect this heritage, the Bahrain Institute for Pearls & Gemstones (DANAT) was established as the…” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 14 | HQ: Basel, SwitzerlandReported employees: 11-50 | Basel, Switzerland | 11-50 | Exact match | 29 contacts → |
“The Swiss Gemmological Institute, part of the Swiss Foundation for the Research of Gemstones (SSEF: Schweizerische Stiftung für Edelstein-Forschung) was founded by trade…” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 15 | HQ: Rozelle, AustraliaReported employees: 51-200 | Rozelle, Australia | 51-200 | Exact match | 28 contacts → |
“The Gemmological Association of Australia (GAA) is Australia’s long established gemmological educator.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 16 |  Ggtl Laboratories Switzerlandggtl-lab.orgHQ: Geneva, SwitzerlandReported employees: 11-50 | Geneva, Switzerland | 11-50 | Exact match | 26 contacts → |
“GGTL Laboratories is the merging of two laboratories: GemTechLab, founded in 1996 by Franck Notari in Geneva, Switzerland and GEMLAB (Liechtenstein), founded in 1996 by Thomas…” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 17 |  ICA Gemlabicagemlab.comHQ: Bangkok, ThailandReported employees: 11-50 | Bangkok, Thailand | 11-50 | Exact match | 25 contacts → |
“ICA | GemLab is an expert in identification, origin determination, and treatment detection for colored gemstones.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 18 | HQ: Istanbul, TürkiyeReported employees: 51-200 | Istanbul, Türkiye | 51-200 | Exact match | 24 contacts → |
“Yolculuğumuz, 10 yılı aşkın süredir yüzbinlerce pırlantayı derecelendiren uzman gemologların bir araya gelmesiyle başladı.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 19 |  Akarsh Exportsakarshexports.comHQ: Mumbai, IndiaReported employees: 11-50 | Mumbai, India | 11-50 | Exact match | 21 contacts → |
“We specialize in GIA certified diamonds with a choice of 6,500+ stones with AI technology of Auto Answering and 24*7 @Bot helpline to serve all our customers regardless of time…” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 20 |  Gubelin GEM LABgubelingemlab.comHQ: Lucerne, SwitzerlandReported employees: 11-50 | Lucerne, Switzerland | 11-50 | Exact match | 20 contacts → |
“The Gübelin Gem Lab was founded in 1923 as a small gemmological laboratory to examine and determine the authenticity of the stones used in Gübelin’s jewellery.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 21 | AIGSaigsthailand.com HQ: Bangkok, ThailandReported employees: 11-50 | Bangkok, Thailand | 11-50 | Exact match | 20 contacts → |
“The Asian Institute of Gemological Sciences (AIGS) was founded in 1978 as South East Asia’s first international gemological education facility.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 22 |  ZCOVAzcova.comHQ: Petaling Jaya, MalaysiaReported employees: 1-10 | Petaling Jaya, Malaysia | 1-10 | Exact match | 19 contacts → |
“At ZCOVA, we modernise the way consumers purchase Diamonds, Coloured Gemstones, and Jewellery.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 23 |  Alpha Minerals Brasilalphaminerals.com.brHQ: United StatesReported employees: 11-50 | United States | 11-50 | Exact match | 19 contacts → |
“Um ecossistema 360º de serviços especializados para o mercado de joias, gemas e metais preciosos.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 24 |  Maison Piatpiat.comHQ: Paris, FranceReported employees: 11-50 | Paris, France | 11-50 | Exact match | 17 contacts → |
“Maison PIAT specializes in the search and cut of natural colored and non-treated gemstones.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 25 |  Labon LLClabondiamonds.comHQ: New York, United StatesReported employees: 11-50 | New York, United States | 11-50 | Exact match | 17 contacts → |
“Labon Diamonds” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
Showing 25 of 845 company matches
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Gemstone certification services: dataset insights
November 6, 2026These summaries describe recorded coverage in this saved dataset. This page is derived from saved source records; per-contact mobile coverage and email-recency results are not established by this snapshot.
Reported company sizes
839 records in the displayed employee bands.
6 matching records are outside the displayed bands or do not have a displayed size. Bars show shares of the displayed bands.
Email recency for this list is measured across the whole country list rather than for Worldwide, so it is reported there. Company counts and contact totals on this page are exact for Worldwide, over 845 companies.
How this company list was built
Describe a niche in your own words: companies installing commercial solar, or manufacturers of sustainable packaging. RevenueBase SmartSearch finds companies whose compiled business descriptions match by meaning. This list is one saved example to adapt.
Where the company descriptions come from
RevenueBase compiles company information from public sources, including company websites and public professional profiles such as LinkedIn, alongside information supplied by companies. The short recorded excerpt shown here is separate from the complete business description used for matching; individual source URLs and collection dates are not provided in this public snapshot.
RevenueBase SmartSearch matching settings
- Exact
- Closest fits to the business described.
- Similar
- Similar businesses with a wider range of fits.
- Related
- Related businesses in and around the category.
- Broad
- A broader set of businesses connected to the description.
RevenueBase SmartSearch · Exact match identifies inclusion in this search's closest semantic matching setting. It is not a per-company confidence score, a literal keyword match, or a quality endorsement.
Selection, ordering and scope
The public list shows selected company records with contact and verified-email coverage. Reported employee bands provide separate company-size context.
This page is derived from saved source records; per-contact mobile coverage and email-recency results are not established by this snapshot.
Recorded company descriptions support research; check company websites for current services. The selected preview is ordered by tracked contacts and is not a list of the best service providers.
Snapshot: November 6, 2026.
RevenueBase is a B2B data infrastructure company. Its September 3, 2026 published methodology describes a graph of 60 million companies and 398.9 million professional contacts; these platform figures differ from this page's totals. Published methodology ↗
Gemstone certification services by location
3 lists · largest firstEvery Gemstone certification services list RevenueBase publishes, by country and city. Counts are matching companies in each list as of its own refresh date.
Countries
- Gemstone certification services based in India191
- Gemstone certification services based in the United States116
Cities
Questions about this company list
What does Exact match mean for gemstone certification services?
The separate RevenueBase SmartSearch column identifies inclusion at the closest semantic matching preset. It is not a literal keyword match, a per-company confidence score or a quality endorsement. Changing the search form opens a new search in RevenueBase; it does not reclassify these saved rows.
How many gemstone certification services did RevenueBase find worldwide?
The saved snapshot records 845 matching company records, 8,111 tracked contacts and 2,027 verified emails. The public preview displays 25 selected records.
Where do the company descriptions come from?
RevenueBase compiles company information from public sources, including company websites and public professional profiles such as LinkedIn, alongside information supplied by companies. The short recorded excerpt shown here is separate from the complete business description used for matching; individual source URLs and collection dates are not provided in this public snapshot.
How are the public companies ordered?
The selected public records are ordered by contacts tracked in RevenueBase, highest first. Contact coverage is a prospecting measure, not an assessment of the company's services or quality.
How can I get contact information?
Select a company's contact count to open its filtered contacts in RevenueBase. Free signup is required and includes 500 credits and limited free results. Verified emails, direct dials and mobile numbers depend on available coverage.
How current is this list?
Snapshot: November 6, 2026. Review each company's website for current services and locations. A recorded business description does not establish that every company offers every service named in the search.
What do headquarters and employee bands mean?
These are recorded company-level fields, rather than a map of every branch or a count of specialists. Missing headquarters or employee bands are labeled; older records may show a location separately from recorded headquarters.
Build your next target company list
Adapt this niche search and work with available contacts in RevenueBase.
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Cite this list
RevenueBase Data Team. Top 25 gemstone certification services worldwide. Snapshot: November 6, 2026. https://revenuebase.ai/companies/browse/gemstone-certification-services.
This is a selected public preview of saved company records, rather than an independently verified census. Open the source page ↗
More company lists
Company intelligence · public preview
Top 25 gemstone certification services worldwide
RevenueBase records 845 matching company records for gemstone certification services worldwide, with 8,111 tracked contacts and 2,027 verified work emails.
This public preview shows 25 selected records ordered by tracked contacts. RevenueBase SmartSearch finds company descriptions that match by meaning at Exact. Snapshot: November 6, 2026.
RevenueBase compiles business descriptions for niche-company discovery; each row shows a recorded excerpt where available. Adapt this search to find the companies and contacts you want.
Top 25 gemstone certification services worldwide
The public list shows selected company records with contact and verified-email coverage. Reported employee bands provide separate company-size context.
| # | Company | Headquarters on record | Reported employees | RevenueBase SmartSearch | Tracked contacts |
|---|---|---|---|---|---|
| 1 | HQ: New York, CA, United StatesReported employees: 501-1,000 | New York, CA, United States | 501-1,000 | Exact match | 385 contacts → |
“IGI, a Blackstone portfolio company, is the world’s largest independent provider of gemological services.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 2 | HRD Antwerphrdantwerp.com HQ: Antwerp, BelgiumReported employees: 201-500 | Antwerp, Belgium | 201-500 | Exact match | 260 contacts → |
“HRD Antwerp is the leading authority when it comes to Diamond Grading, Jewellery Grading and Education.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 3 | SGL Labssgl-labs.com HQ: London, United KingdomReported employees: 201-500 | London, United Kingdom | 201-500 | Exact match | 193 contacts → |
“Peace of mind, Assured.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 4 | Gemological Science International GSIgemscience.net HQ: Manhattan, United StatesReported employees: 51-200 | Manhattan, United States | 51-200 | Exact match | 161 contacts → |
“Gemological Science International (GSI) is one of the largest gemological laboratories with 13 offices in the United States, India, UAE, Hong Kong and Thailand.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 5 | gempundit.comgempundit.com HQ: Gurgaon, IndiaReported employees: 201-500 | Gurgaon, India | 201-500 | Exact match | 127 contacts → |
“GemPundit is one of the leading providers of Luxury, Precious & Semi-Precious Gemstones.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 6 | Ankit Gemsankitgems.com HQ: Mumbai, IndiaReported employees: 1,001-5,000 | Mumbai, India | 1,001-5,000 | Exact match | 127 contacts → |
“A dream company started by three visionaries; Arvind Shah, Arun Shah and Dilip Shah in 1985, was then strengthened by Vasant Shah, Pravin Shah and Dilip Soni, bringing together…” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 7 | Gemsnygemsny.com HQ: Fort Lee, NJ, United StatesReported employees: 51-200 | Fort Lee, NJ, United States | 51-200 | Exact match | 83 contacts → |
“GemsNY is your trusted source for untreated, certified natural color gemstones and custom fine jewelry.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 8 | Birmingham Assay Officetheassayoffice.com HQ: Birmingham, United KingdomReported employees: 51-200 | Birmingham, United Kingdom | 51-200 | Exact match | 66 contacts → |
“The Birmingham Assay Office was founded in 1773 to provide Assaying (testing) and Hallmarking of precious metal items (Gold, Silver, Platinum and Palladium) as required by the…” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 9 | IDT Gemological Laboratories Worldwideidtworldwide.com HQ: United StatesReported employees: 51-200 | United States | 51-200 | Exact match | 61 contacts → |
“IDT is among the premier networks of Gemological Laboratories, which empowers and enables jewellers, jewellery brands, manufacturers, wholesalers, end-use customers and the masses…” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 10 | Pansuriya Impex HK LTDpansuriyaimpex.com HQ: IndiaReported employees: 1,001-5,000 | India | 1,001-5,000 | Exact match | 52 contacts → |
“we are manufacturer of GIA / IGI / AGA certified diamonds from 0.30cts to 15 carats.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 11 | Gem-Agem-a.com HQ: London, United KingdomReported employees: 11-50 | London, United Kingdom | 11-50 | Exact match | 51 contacts → |
“Creating and supporting gemmologists since 1908.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 12 | RDI Diamonds INCrdidiamonds.com HQ: Rochester, NY, United StatesReported employees: 51-200 | Rochester, NY, United States | 51-200 | Exact match | 50 contacts → |
“America's Diamond Specialist - Memo and Stock Quality, attention to detail, honesty, fairness, and on-time delivery.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 13 | HQ: Manama, BahrainReported employees: 11-50 | Manama, Bahrain | 11-50 | Exact match | 48 contacts → |
“As a reflection of Bahrain’s ancient pearling history and the strong desire to protect this heritage, the Bahrain Institute for Pearls & Gemstones (DANAT) was established as the…” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 14 | HQ: Basel, SwitzerlandReported employees: 11-50 | Basel, Switzerland | 11-50 | Exact match | 29 contacts → |
“The Swiss Gemmological Institute, part of the Swiss Foundation for the Research of Gemstones (SSEF: Schweizerische Stiftung für Edelstein-Forschung) was founded by trade…” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 15 | HQ: Rozelle, AustraliaReported employees: 51-200 | Rozelle, Australia | 51-200 | Exact match | 28 contacts → |
“The Gemmological Association of Australia (GAA) is Australia’s long established gemmological educator.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 16 | Ggtl Laboratories Switzerlandggtl-lab.org HQ: Geneva, SwitzerlandReported employees: 11-50 | Geneva, Switzerland | 11-50 | Exact match | 26 contacts → |
“GGTL Laboratories is the merging of two laboratories: GemTechLab, founded in 1996 by Franck Notari in Geneva, Switzerland and GEMLAB (Liechtenstein), founded in 1996 by Thomas…” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 17 | ICA Gemlabicagemlab.com HQ: Bangkok, ThailandReported employees: 11-50 | Bangkok, Thailand | 11-50 | Exact match | 25 contacts → |
“ICA | GemLab is an expert in identification, origin determination, and treatment detection for colored gemstones.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 18 | HQ: Istanbul, TürkiyeReported employees: 51-200 | Istanbul, Türkiye | 51-200 | Exact match | 24 contacts → |
“Yolculuğumuz, 10 yılı aşkın süredir yüzbinlerce pırlantayı derecelendiren uzman gemologların bir araya gelmesiyle başladı.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 19 | Akarsh Exportsakarshexports.com HQ: Mumbai, IndiaReported employees: 11-50 | Mumbai, India | 11-50 | Exact match | 21 contacts → |
“We specialize in GIA certified diamonds with a choice of 6,500+ stones with AI technology of Auto Answering and 24*7 @Bot helpline to serve all our customers regardless of time…” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 20 | Gubelin GEM LABgubelingemlab.com HQ: Lucerne, SwitzerlandReported employees: 11-50 | Lucerne, Switzerland | 11-50 | Exact match | 20 contacts → |
“The Gübelin Gem Lab was founded in 1923 as a small gemmological laboratory to examine and determine the authenticity of the stones used in Gübelin’s jewellery.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 21 | AIGSaigsthailand.com HQ: Bangkok, ThailandReported employees: 11-50 | Bangkok, Thailand | 11-50 | Exact match | 20 contacts → |
“The Asian Institute of Gemological Sciences (AIGS) was founded in 1978 as South East Asia’s first international gemological education facility.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 22 | ZCOVAzcova.com HQ: Petaling Jaya, MalaysiaReported employees: 1-10 | Petaling Jaya, Malaysia | 1-10 | Exact match | 19 contacts → |
“At ZCOVA, we modernise the way consumers purchase Diamonds, Coloured Gemstones, and Jewellery.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 23 | Alpha Minerals Brasilalphaminerals.com.br HQ: United StatesReported employees: 11-50 | United States | 11-50 | Exact match | 19 contacts → |
“Um ecossistema 360º de serviços especializados para o mercado de joias, gemas e metais preciosos.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 24 | Maison Piatpiat.com HQ: Paris, FranceReported employees: 11-50 | Paris, France | 11-50 | Exact match | 17 contacts → |
“Maison PIAT specializes in the search and cut of natural colored and non-treated gemstones.” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
| 25 | Labon LLClabondiamonds.com HQ: New York, United StatesReported employees: 11-50 | New York, United States | 11-50 | Exact match | 17 contacts → |
“Labon Diamonds” Recorded description excerpt · November 6, 2026Open company data in RevenueBase ↗Free signup required. | |||||
Showing 25 of 845 company matches
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Gemstone certification services: dataset insights
November 6, 2026These summaries describe recorded coverage in this saved dataset. This page is derived from saved source records; per-contact mobile coverage and email-recency results are not established by this snapshot.
Reported company sizes
839 records in the displayed employee bands.
6 matching records are outside the displayed bands or do not have a displayed size. Bars show shares of the displayed bands.
Email recency for this list is measured across the whole country list rather than for Worldwide, so it is reported there. Company counts and contact totals on this page are exact for Worldwide, over 845 companies.
How this company list was built
Describe a niche in your own words: companies installing commercial solar, or manufacturers of sustainable packaging. RevenueBase SmartSearch finds companies whose compiled business descriptions match by meaning. This list is one saved example to adapt.
Where the company descriptions come from
RevenueBase compiles company information from public sources, including company websites and public professional profiles such as LinkedIn, alongside information supplied by companies. The short recorded excerpt shown here is separate from the complete business description used for matching; individual source URLs and collection dates are not provided in this public snapshot.
RevenueBase SmartSearch matching settings
- Exact
- Closest fits to the business described.
- Similar
- Similar businesses with a wider range of fits.
- Related
- Related businesses in and around the category.
- Broad
- A broader set of businesses connected to the description.
RevenueBase SmartSearch · Exact match identifies inclusion in this search's closest semantic matching setting. It is not a per-company confidence score, a literal keyword match, or a quality endorsement.
Selection, ordering and scope
The public list shows selected company records with contact and verified-email coverage. Reported employee bands provide separate company-size context.
This page is derived from saved source records; per-contact mobile coverage and email-recency results are not established by this snapshot.
Recorded company descriptions support research; check company websites for current services. The selected preview is ordered by tracked contacts and is not a list of the best service providers.
Snapshot: November 6, 2026.
RevenueBase is a B2B data infrastructure company. Its September 3, 2026 published methodology describes a graph of 60 million companies and 398.9 million professional contacts; these platform figures differ from this page's totals. Published methodology ↗
Gemstone certification services by location
3 lists · largest firstEvery Gemstone certification services list RevenueBase publishes, by country and city. Counts are matching companies in each list as of its own refresh date.
Countries
- Gemstone certification services based in India191
- Gemstone certification services based in the United States116
Cities
Questions about this company list
What does Exact match mean for gemstone certification services?
The separate RevenueBase SmartSearch column identifies inclusion at the closest semantic matching preset. It is not a literal keyword match, a per-company confidence score or a quality endorsement. Changing the search form opens a new search in RevenueBase; it does not reclassify these saved rows.
How many gemstone certification services did RevenueBase find worldwide?
The saved snapshot records 845 matching company records, 8,111 tracked contacts and 2,027 verified emails. The public preview displays 25 selected records.
Where do the company descriptions come from?
RevenueBase compiles company information from public sources, including company websites and public professional profiles such as LinkedIn, alongside information supplied by companies. The short recorded excerpt shown here is separate from the complete business description used for matching; individual source URLs and collection dates are not provided in this public snapshot.
How are the public companies ordered?
The selected public records are ordered by contacts tracked in RevenueBase, highest first. Contact coverage is a prospecting measure, not an assessment of the company's services or quality.
How can I get contact information?
Select a company's contact count to open its filtered contacts in RevenueBase. Free signup is required and includes 500 credits and limited free results. Verified emails, direct dials and mobile numbers depend on available coverage.
How current is this list?
Snapshot: November 6, 2026. Review each company's website for current services and locations. A recorded business description does not establish that every company offers every service named in the search.
What do headquarters and employee bands mean?
These are recorded company-level fields, rather than a map of every branch or a count of specialists. Missing headquarters or employee bands are labeled; older records may show a location separately from recorded headquarters.
Build your next target company list
Adapt this niche search and work with available contacts in RevenueBase.
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Cite this list
RevenueBase Data Team. Top 25 gemstone certification services worldwide. Snapshot: November 6, 2026. https://revenuebase.ai/companies/browse/gemstone-certification-services.
This is a selected public preview of saved company records, rather than an independently verified census. Open the source page ↗