What is an IGI certificate

What is an IGI Certificate and Why It Matters When You Buy a Diamond

What is an IGI Certificate and Why It Matters When You Buy a Diamond

Short answer: an IGI certificate is an independent lab report that documents a diamond’s true technical characteristics — critical for transparency and long-term value.

What is an IGI certificate?

IGI (International Gemological Institute) issues independent gemological reports that list a diamond’s weight (carat), cut grade, color grade, clarity grade, measurements, proportion diagrams, and any treatments or identifying marks. This report is the technical fingerprint of the stone.

The 4Cs: Cut, Color, Clarity, Carat

IGI records the 4Cs using industry-accepted scales. Quick breakdown:

AttributeWhat it measuresWhy it matters
CutPrecision of the faceting and proportionsDetermines brilliance and perceived size — most important for beauty.
ColorFrom D (colorless) to ZLess color generally increases value; H–I often look white once set.
ClarityPresence of inclusions or blemishesAffects appearance; VS–SI often "eye-clean".
CaratWeight of the diamondDrives price but doesn't replace poor cut.

Store certificate vs lab report

Important distinction:

  • Store/vendor certificate: created by the retailer; often concise and sales-focused. It can be useful for store policies but is not an independent verification.
  • Laboratory report (IGI, GIA, HRD): independent, standardized and intended to be objective and verifiable. This is the report used by professionals and resellers.

Rule: treat store certificates as warranty/receipt documents, not as a substitute for an independent lab report.

A short history of IGI

Founded in 1975, IGI grew into one of the world’s largest gemological institutions with laboratories in Antwerp, New York, Hong Kong and Shanghai. IGI was an early lab to formalize grading for lab-grown diamonds in addition to natural stones and provides an online verification system for reports.

Why an IGI certificate matters to you

  • Independence: It’s issued by a third party, not the merchant.
  • Comparability: Standardized grades let you compare stones across sellers.
  • Resale & insurance: Insurers and secondary buyers accept lab reports far more readily than vendor certificates.
  • Identification: IGI notes treatments, laser inscriptions, and whether a stone is lab-grown or natural.
Quick tip: ask for the IGI report number and verify it on IGI’s website before completing the purchase.
View IGI-Certified Diamonds

⚠️ Note: This article is informational and not legal or financial advice.


Съдържанието на този уебсайт, включително текстове, графики, изображения и други материали, е информативно и не представлява консултация, препоръка или съвет за вземане на инвестиционно решение, тъй като не отчита вашите индивидуални финансови обстоятелства, нужди и цели.

Инвестирането носи рискове, включително възможността за загуба на вложени средства и не гарантира положителна възвращаемост. Съдържанието на този уебсайт не представлява оферта или препоръка за използването на даден инвестиционен продукт или услуга. Препоръчително е да се консултирате с финансов консултант или специалист преди да вземете решение по финансови въпроси.

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