Company lists · Data refreshed November 2026

Top 25 Diamond certification labs worldwide

RevenueBase identified 675 company matches for diamond certification labs worldwide as of November 2026 and tracks 8,741 professional contacts across them, including 2,181 with verified work emails. India is the largest market and Surat the largest hub.

This list covers company matches for diamond certification labs 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 diamond certification labs 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.

How to read this list RevenueBase SmartSearch · Exact Recorded Nov 6, 2026 How this list was built
675Companies
8,741Contacts tracked
2,181Verified emails
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The 25 largest diamond certification labs worldwide

Ranked by team size
Top 25 of 675 company matches for diamond certification labs worldwide, ordered by professional contacts tracked in RevenueBase, largest first. Recorded Nov 6, 2026. The RevenueBase SmartSearch column shows Exact match membership in this saved search. Click a contact count to view that company's people. Totals use company locations recorded by RevenueBase; the displayed preview is a smaller selection.
#CompanyRevenueBase SmartSearchHeadquartersEmployeesContacts
1Exact matchNew York, CA, United StatesHQ recorded Nov 6, 2026501-1,000385 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
2Exact matchAntwerp, BelgiumHQ recorded Nov 6, 2026201-500260 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
3Exact matchZoutleeuw, BelgiumHQ recorded Nov 6, 20261,001-5,000197 contacts →

Exact match

Recorded description not available.

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
4Exact matchNew York, NY, United StatesHQ recorded Nov 6, 202651-200194 contacts →

Exact match

“Founded in 2016 by a former BCG consultant frustrated with his own engagement ring buying experience, Rare Carat began with a mission to make diamond buying more transparent for…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
5Exact matchLondon, United KingdomHQ recorded Nov 6, 2026201-500193 contacts →

Exact match

“Peace of mind, Assured.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
6Exact matchManhattan, United StatesHQ recorded Nov 6, 202651-200161 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
7Exact matchİstanbul, TürkiyeHQ recorded Nov 6, 20261,001-5,000161 contacts →

Exact match

“Blue Diamond, 2004 yılında toptancı bir firma olarak, mücevher sektörüne pırlanta tedarik etmek ve sektörü pırlanta konusunda eğitmek amacıyla kuruldu.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
8Exact matchMumbai, IndiaHQ recorded Nov 6, 20261,001-5,000127 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
9Exact matchMumbai, IndiaHQ recorded Nov 6, 20261,001-5,000110 contacts →

Exact match

“To join our family, fill this form for us to know you better - https://forms.gle/mMD8d1hP3NHWJmr59 Founded by brothers Mr.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
10Exact matchMumbai, IndiaHQ recorded Nov 6, 2026501-1,00097 contacts →

Exact match

“Star Rays is a diamond manufacturer who are passionate about their products and solely focused on the diamond industry.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
11Exact matchPune, IndiaHQ recorded Nov 6, 2026201-50075 contacts →

Exact match

“Welcome to The Solitario - Elevate Your Elegance with Diamonds At The Solitario Lab Grown Diamonds, we're in the business of crafting dreams and turning moments into cherished…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
12Exact matchIndiaHQ recorded Nov 6, 2026501-1,00073 contacts →

Exact match

Recorded description not available.

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
13Exact matchSurat, IndiaHQ recorded Nov 6, 20261,001-5,00071 contacts →

Exact match

“Greenlab Diamonds is the world’s largest lab-grown Diamond Cultivator.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
14Exact matchUnited StatesHQ recorded Nov 6, 2026501-1,00065 contacts →

Exact match

Recorded description not available.

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
15Exact matchUnited StatesHQ recorded Nov 6, 202651-20061 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
16Exact matchIndiaHQ recorded Nov 6, 20261,001-5,00052 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
17Exact matchMumbai, IndiaHQ recorded Nov 6, 20261,001-5,00051 contacts →

Exact match

“Welcome to Paladiya Brothers & Co, we pride ourselves on being a trusted name in the diamond industry, offering exceptional quality and unparalleled service.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
18Exact matchRochester, NY, United StatesHQ recorded Nov 6, 202651-20050 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
19Exact matchChicago, IL, United StatesHQ recorded Nov 6, 202651-20046 contacts →

Exact match

“We partner with you.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
20Exact matchSydney, AustraliaHQ recorded Nov 6, 202611-5045 contacts →

Exact match

“At Novita Diamonds, we are dedicated to providing our customers with beautiful, high quality lab grown diamond jewellery using diamonds that are ethically sourced, conflict-free…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
21Exact matchIndiaHQ recorded Nov 6, 202611-5040 contacts →

Exact match

Recorded description not available.

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
22Exact matchSurat, IndiaHQ recorded Nov 6, 2026501-1,00040 contacts →

Exact match

“Welcome to Mira Gems, a leading lab-grown diamond company dedicated to providing sustainable, ethical, and exquisite diamonds.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
23Exact matchAtlanta, NY, United StatesHQ recorded Nov 6, 202611-5036 contacts →

Exact match

“Ascot Diamonds is a jewelry store with locations in Atlanta, Washington DC, Dallas, New York, Charlotte, Charleston SC, and Philadelphia.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
24Exact matchSurat, IndiaHQ recorded Nov 6, 2026201-50035 contacts →

Exact match

“With an unwavering commitment to environmental preservation, Sonani Jewels embrace the art of growing exquisite diamonds that embody both eco-friendliness and ethical integrity.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
25Exact matchMumbai, IndiaHQ recorded Nov 6, 202611-5034 contacts →

Exact match

“Welcome to Firefly Diamonds, where brilliance meets sustainability!”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase

Showing 25 of 675 diamond certification labs worldwide

See the full list, filter by size, metro and specialty, and access 2,181 tracked professional contacts with verified work emails. Direct dials are available where recorded.

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Diamond certification labs worldwide at a glance

As of Nov 6, 2026
25.0%Verified-email coverage
12.9Average contacts per company
1-10Median size (employees)
11.9%Largest-city concentration · Surat
Nov 6, 2026Page data refreshed

Companies by employee count

1-10
341
11-50
191
51-200
74
201-500
25
501-1,000
19
1,001-5,000
13

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 diamond certification labs are linked below.
What qualifies
Company records worldwide whose business descriptions match “diamond certification labs” 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 2,181 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.

Diamond certification labs by location

5 lists · largest first

Every Diamond certification labs list RevenueBase publishes, by country and city. Counts are matching companies in each list as of its own refresh date.

Countries

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 “diamond certification labs”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many diamond certification labs are there worldwide?

RevenueBase identified 675 company matches for diamond certification labs 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 diamond certification labs?

India leads with 215 companies, followed by the United States (134). Every diamond certification labs list by country and city is linked on this page.

Which city has the most diamond certification labs?

Surat leads with 80 company records, followed by New York (64) and Mumbai (59).

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 2,181 professional contacts with verified work emails tracked across these 675 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.

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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.