ISO 24016 - Globally Consistent Diamond Grading Standard
A clear, expert guide from the Monroe Yorke Diamonds team.
A very big leap for globally consistent diamond grading standards. The International Standards Organization (ISO) has sanctioned its very first grading standards for polished diamonds in an effort to achieve uniformity among diamond grading laboratories.
The ISO 24016 has clearly specified classification, terminology and methods, diamond grading laboratories should be using when grading polished loose diamonds.
ISO stated “Some diamond-grading reports may be issued based on different standards by different laboratories, potentially leading to different results for the same individual diamond … This situation damages the reputation of the whole diamond trade. Hence the need for a unique ISO standard for grading polished diamonds.”
This inconsistency in diamond grading has been a problem encountered by reputable diamond dealers for many years. Customers compare cheaper diamonds sold with certain diamond grading laboratories that inflate a diamond’s true colour, clarity and cut grades, with diamonds graded by reputable diamond grading laboratories like GIA and AGS. These incorrectly graded diamonds seem to be a lot cheaper than a similar diamond that has been correctly graded. In reality a customer is paying an inflated price for a lower quality diamond.
This new standard only applies to natural unmounted polished diamonds with a weight of 0.25 carats and higher. The standard does not apply to fancy coloured diamonds, treated diamonds or lab-grown diamonds.
Monroe Yorke Diamonds only use diamonds graded by GIA. Read more about GIA Certified Diamonds from Monroe Yorke Diamonds
Read the detaisl of the standard
ISO 24016:2020
Jewellery and precious metals — Grading polished diamonds — Terminology, classification and test methods
Written & reviewed by the Monroe Yorke Diamonds team
We have spent 20 years helping Australians choose diamonds, with appointment-only studios in Sydney, Melbourne, Brisbane and Perth.
Frequently asked questions
Ready to find your ring?
Browse the collection, or book a private appointment and let our specialists guide you.
Buying Guide
03 Jun 2026
Diamond Quality Facts
Every diamond is unique. This is a beautiful fact about the most exquisite mineral in the world. They are not...
22 Sep 2025
The Strategic Purchase: Choosing Between a Loose Diamond and a Pre-Set Ring
The Strategic Purchase: Choosing Between a Loose Diamond and a Pre-Set Ring Choosing the perfect engagement ring is a deeply...
22 Sep 2025
The Definitive Guide to Lab-Grown Diamonds
The world of diamonds is evolving, and lab-grown diamonds are at the forefront of this new era of conscious luxury....
