---
title: "Laboratory-Grown Diamond Quality Assessment: meaning in gemology"
description: "GIA's Laboratory-Grown Diamond Quality Assessment rates a lab-grown diamond Premium or Standard. It replaced GIA's D-to-Z lab-grown reports on 1 October 2025."
url: https://digitalgemology.com/learn/glossary/laboratory-grown-diamond-quality-assessment
image: https://digitalgemology.com/img/og-digital-gemology.png?v=d224fb01
---

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[Glossary](https://digitalgemology.com/learn/glossary) · Grading report

# Laboratory-Grown Diamond Quality Assessment

Also called GIA lab-grown diamond assessment, Premium or Standard

GIA's Laboratory-Grown Diamond Quality Assessment rates a lab-grown diamond Premium or Standard. It replaced GIA's D-to-Z lab-grown reports on 1 October 2025.

## In more detail

It covers loose, colorless to near-colorless lab-grown diamonds of 0.15 ct or more. GIA gave its reason: most lab-grown diamonds fall in a very narrow range of color and clarity. Premium needs D color, VVS clarity or higher, Excellent polish and symmetry, and Excellent cut for a round. A stone below the Standard minimums gets no assessment.

## On a grading report

The assessment states Premium or Standard, not a color or clarity grade. GIA inscribes "Laboratory-Grown" and the assessment number on the girdle.

## Related terms

- [Laboratory-grown diamond](https://digitalgemology.com/learn/glossary/laboratory-grown-diamond): A laboratory-grown diamond is a diamond that people grow with machines, by HPHT or CVD. It has essentially the same composition, crystal structure and properties as a natural diamond.
- [Laboratory-Grown Diamond Report](https://digitalgemology.com/learn/glossary/laboratory-grown-diamond-report): The Laboratory-Grown Diamond Report was GIA's digital-only report for laboratory-grown diamonds, from October 2020 to September 2025. It gave color and clarity grades and stated the growth method, CVD or HPHT.
- [Diamond grading report](https://digitalgemology.com/learn/glossary/diamond-grading-report): A diamond grading report is an independent lab's record of what a stone is and how it grades. It is true for the day the lab examined the stone.
- [Inscription](https://digitalgemology.com/learn/glossary/inscription): An inscription is text that a laser writes on the girdle of a stone, too small to see without magnification. Most often it is the report number.

[All 328 terms](https://digitalgemology.com/learn/glossary)