The Gemological Institute of America (GIA) has announced changes to its grading services for D-to-Z laboratory-grown diamonds, effective from 1 October 2025. Current GIA services for these diamonds will remain available until 30 September.
New Assessment Structure
Under the updated framework, GIA will no longer apply the natural diamond grading system to laboratory-grown diamonds. Instead, stones will be categorised as either ‘Premium’ or ‘Standard’ based on combined evaluations of clarity, colour and cut.
Pritesh Patel, GIA president and CEO, stated: “Using descriptive terms for the quality of laboratory-grown diamonds is appropriate as most fall into a very narrow range of color and clarity. Because of that, GIA will no longer use the nomenclature created for natural diamonds to describe what is a manufactured product.”
Criteria for Assessment
Diamonds that meet all of the following criteria will be classified as ‘Premium’:
- Clarity: Very, Very Slightly Included (VVS) or higher
- Colour: D
- Polish and symmetry: Excellent
- Cut grade: Excellent (round brilliant cuts only)
Diamonds meeting a combination of some ‘Premium’ criteria and the following minimum requirements will receive a ‘Standard’ classification:
- Clarity: Very Slightly Included (VS)
- Colour: E to J
- Polish: Very Good
- Symmetry: Very Good (or Good for fancy shapes)
- Cut grade: Very Good (round brilliant cuts only)
Stones that do not meet the minimum criteria for the ‘Standard’ classification will not receive a quality assessment.
Fees and Documentation
The GIA will charge US$15 per carat for the new Laboratory-Grown Diamond Quality Assessment, with a minimum charge of $15. Submissions not meeting the minimum criteria will be subject to a $5 evaluation fee. The minimum stone size accepted is 0.15 carats.
Each assessed stone will be laser inscribed on the girdle with the phrase “Laboratory-Grown” alongside the GIA assessment number. A printed report will accompany each stone.
